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Vision Engineering Publications VISION ENGINEERING ACADEMY, PUNE

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CHAPTER 1 : THERMODYNAMICS ============================================================================================ Thermodynamics : It is the branch of science which deals with two forms of energy. 1)

Heat

2)

Work & their conversion into each other Heat 

Low grade energy

Work 

High grade energy

Heat 

Work – e.g Ic engines, powerplants.

(Very diffcult) Work 

(Thermal, nuclear, solar, gas turbine)

Heat – e.g. Mechanical brakes

(Very easy) Ideal Gas : It is the gas which obeys all the laws at all pressures & temperature e.g. Air Gas Laws : 1)

Boyle’s Law :

Pα

1 (T  C, m  c) V

V1 > V2

P

V2

V1

V  when P 

m

PV α 1

P = Pressure V = Volume m = mass

PV = C

P1V1 = P2V2 2)

Charle’s Law : P α T T = Temperature of the gas. Combine Boyle’s law & charles law

Pα

T V

PV α c T

P1V1 P2V2   IdealGas equation T1 T2 For a gas of mass (m)

PV αm T VISION ENGINEERING ACADEMY, PUNE

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PV α mT PV = mRT another form of ideal gas R = characteristics gas constant, kj/kg.k Thermodynamic Work : Work = force × displacement

P

F A

δW  P.dx



F  P.A

δW  P.dV Volume dv

Total work (W) =  δW   ρ dv W   p.dv

Types of Properties : 1)

Intensive Properties : The properties which are independant of mass are called intensive properties e.g. Pressure (P) Temperature (T), Density ( ρ )

 N.S  Viscosity ( μ ).   . Thermal conductivity (k)  m²  2)

Extensive Properties : The properties which are dependant on mass are called extensive properties. e.g. Volume (V), Enthalpy (h), Internal energy (u) Types of Thermodynamic Process : a)

Law of conservation of energy Also known as quantitative law

Change in Heat supplied

Q = 100 KJ Int. energy W.D by system

Q  W  U

Work done

Q+W  ΔU V



W V1

V2

W.D on system

1 ρ

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Note : Both intensive & extensive prop are point function Isochoric Process / Constant Volume Process W   P.dv W=0

P1 P2  T1 T2

Ideal gas equation for isochoric process

1

2

2

1

P

V

b)

Isobaric Process or constant pressure process : W   P.dv W = P (V2 – V1)

(1)

Q  P (V2  V1 )  ΔU

(2)

Q – P (V2 – V1) = U2 – U1

(3)

V1 V2  T1 T2

Ideal Gas equation

1

2

2

1

P

V

C)

Isothermal process or constant temperature process (T = C) P1V1  P2 V2   PV  constant 

Ideal Gas equation

x.y = c, - Hyperbola equation VISION ENGINEERING ACADEMY, PUNE

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2 1 P

PV = C

1 2 V

PV = P1V1 = P2V2 P = P1V1 PV W 1 1 V

V2

dv  P1V1

 V1

dv V

V  W  P1V1 n  2   V1 

Imp

(1)

P  W  P1V1 n  1   P2 

Imp

(2)

PV = mRT P1V1 = mRT1

P2V2 = mRT2

P  W  mRT1 n  1   P2 

(3)

V  W  mRT2 n  2   V1 

d)

(4)

Adiabatic Process : Q = 0 Q  W  U  U 2  V1 – W = U2 – U1 W = U1 – U2

2 1 P

r

PV = C

1 2 V VISION ENGINEERING ACADEMY, PUNE

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P  Vr  C

r  adiabatic Index 

CP CV

CP = Specific heat at constant pressure CV = Specific heat at constant volume Note :

Specific Heat : The amount of hat reqd to increase the temp. of unit mass of a gab by 1°c is called specific heat. Ti

P=C

 T by 1° C 1 kg



For Air :

CP = 1.005 KJ/kg.k

R = 0.287 KJ/kg.k

CV = 0.718 KJ/kg.k CP – CV = R P.Vr = C = P1V1r = P2V2r

P



Note : 

P1V1r Vr

W   P.dv



W

P1V1  P2 V2 r 1

W

mR(T1  T2 ) r 1

P1V1r  V r dv P1V1  mRT1 P2 V2  mRT2

Adiabatic curve will be more steeper than isothermal curve. Generalised Equation for above 4 process : P.Vk = constant

Note :

1)

k= 

–––

Isochoric process

2)

k=0

–––

Isobaric process

3)

k=1

–––

Isothermal process (T = C)

4)

k=r

–––

Adiabatic process (Q = 0)

W.D in free expansion = 0

Expansion against vaccum – free expansion

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(r) Air 

CP 1.005  CV 0.718

r Air = 1.4 Polytropic Process : P.Vn = constant 1 < n < 1.4

W

P1V1  P2V2 n 1

1 Isothermal P Polytropic 2 Adiabatic

2

2

V



Types of systems :

1)

Closed system : (a) (b)

No mass transfer Only Energy Transfer

e.g. - piston - cylinder arrangement, Automobile car battery 2)

Open system : Both energy as well as mass transfer occurs. e.g - Boiler Turbine, Pump compressor, nozzle, diffusorcondensor.

3)

Isolated system : Neither mass nor energy transfer e.g – Thermos, universe



First law of thermodynamics applied to cyclic precess :

Q  W  U

 Non  cylic

Sign conventions : 1)

Work : Work done by the system  + ve e.g. Turbine Work done on the system  – ve e.g. pump, compressor

2)

Heat : Heat supplied to system  + ve e.g. boiler

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Heat rejected by system  – ve e.g condenser

1 1 P

Q 1 (+) 2

P (–) 2

W2 (+)

W1 4

V

Q2 3 (–) V

Q  W + Q1 – Q2 = + W1 – W2 Statement : For a closed system undergoing the cycle the net heat transer is equal to net work treasfered. i.e. Q  W



CP r CV



 r  CP    R  r CV  r 1 CV 

& C P  CV  R

R r 1

CP  C v Perpetual Motion Machine of First kind (PMMI) –

PMM – I – Violets first law of thermodynamics.

–

PMM – J continuously produces work without other forms of energy disappearing simultaneously. PMM I



W

Point function & path funcctions :

1 P1, V1, T1 3 P

2 P2, V2, T2 V VISION ENGINEERING ACADEMY, PUNE

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Internal energy

H Point function – P, V, T, Enthalpy

U

, S

Entropy

Point function – Thermodynamic properties, state variables, Exact differentials, TD co-ordinates. W

V  P1V1  P2 V2  P1 V1 , n  2  r 1  V1 

V  W  P(V2  V1 )  0  P1V1 n  2   V1 

Heat & Work are path functions or inexact differentials, energy in transition, observed only at boundary. Enthalpy : Denoted by ‘H’ –

It is the sum of internal energy (U) & how flow work (PV)



H = U + PV

Three forms of applications of Ist law of T.D : 1)

Q  W  U

–

Non – cylic

2)

Q  W

–

Cyclic

3)

Open system Steady Flow Energy Equation (SFEE) : Open systems e.g. Tuurbine, Boiler, Compressor, pump, condensor, nozzle, diffuser, Evaporator.

1)

Conservation of mass : Min = Mout ρ1A1V1  ρ 2 A 2 V2

ρ

m kg/s  V m³/s

V

m³ m  m² s s

(1)

= A× V

A1V1 A 2 V2  V1 V2

Open system P1 T1 Volume V1 V1–Volume Z1 H1

(2)

P2 T2 V2 V2 Z2 H2

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2)

Conservation of Energy : Ein = Eout Volume = V Specific volume = V

V

m³ kg

1 U1  P1V1  mV12  mg Z1  Q   2 H1

1 U 2  P2 V2  mV22  mg Z 2  W  2 =  H2



1 1 H1  m V12  mg Z1  Q  H 2  m V22  mg Z2  W 2 2 divide throuthout by m Hence all properties will become specific.

V12 V2  gz1  q  h 2  2  gz 2  w 2 2

(2)



 V 2  V12  q  w  (h 2  h1 )   2   g (z 2  z1 ) 2  

(3)



q  w  h  K.E  P.E

H1 

(4)

Application of SFEE : Steam turbine power plant or thermal power plant : –

Components 1)

Boiler

2)

Steam Turbine

3)

Condensor

4)

Pump

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Superheated steam Shaft Boiler

Qs

Generator

Turbine WT

steam (Low P, Low T) Condenser

water

QR

Works on Rankine cycle

Pump WP

water

For boilers :

h1 

V12 V2  gz1  q  h 2  2  gz 2  0 2 2

For Turbine : For condensor : For pump : 

Second Law of Thermodynamics :

–

Defines a property called as ‘Entropy (s)’

–

Qualitative law (Heat at high temp. has greate quality than the same amount of heat at lower temp.)

A)

Clausius statement : It is impossible to transfer heat from low temp. to high temp. without any external work input. e.g. Refridgerator (without electricity cext work temp inside & outside can not be maintained same.) (by rejecting heat to atm)

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T1

(T1 > T2)

100°C

Refridgerator

Winput

Q abs T2

5°C

–

It works on 3 cyles :

1)

VCR – (Vapour compression refridgerator)

2)

VAR – (Vapour absorption refridgrator)

3)

Bell colemn cycle – or reversed brayton cycle.

Q  W Qabs  Qrej  Winput This is Ist law of TD applied to refridgerator. B)

Kelvin planks statement : It is impossible to develope a device operating on a cycle which produce work while exchanging heat with the single reservoir. [Engine – Any device produce work] T1

Source

T1

Source Q1

Q1 E

Heat engine Q2

Not possible

–

T2

5°C

If such device is passible then it is known as perpetual motion m/c of IInd kind. [PMM–II]

–

Hence according to kelvin -planck statement PMM–II is impossible.

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Efficiency (η)  η Note :

Work done W  Heat supplied Qs

W  Possible Q1

Source – It is the thermal reservoir which has the capacity to supply large amount of heat without undergoing any temp. change. e.g. Sun

Note :

Sink : It is the thermal reservoir which has the capacity to absorb large amount of heat without undergoing and change. e.g. atmoshere Refridgerator And Heat Pump : TH

Qrefrigerator

Refrigerator Heat pump

W input

Qabs 5°C

TL

For refridgerator & heat pump we difine a term called “coefficient of performance” COP 

Desired effect Winput

(COP)ref 

Qabs Qabs  Winp Q rej  Qs

(COP)H.P 

Q rej Qinp

TL = Lower temp TH = Higher temp



Qabs – Qrej = Winp



Qrej = Winp + Qabs



(COP) H.P 

Q abs Winp   1  (COP) ref Winp Winp

(COP) HP  1  (COP) ref VISION ENGINEERING ACADEMY, PUNE

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Refridgerator : Device which maintains a temp as compaired to surrounding temp. Heat Pump :

Device which maintans higher temp as compaired to surrounding temp.

Carnot Cycle : detine for engines Carnot cycle consist of 4 process :

1

Isothermal heat addition 2 (very slow) Adiabatic expansion (very fast) 3

(very fast) Adiabatic compression

P

4

Isothermal heat rejection (very slow)

V

Carnot cycle has 2 adiabatic & 2 isothermal processess. –

Carnot cycle is not practical cycle.

–

Used only to compare with other cycle. It is only a Ideal curve. T= C

1

T1

2

T T2

4

S=C

3

S=C

S

ηcarnot cycle  Maximum ηmax  η

–

carnot cycle = 1

T2 T1

Efficiency of carnot cycle depends only on temp limits. It does not depends upon working fluid.

–

Carnot cycle is a reversible cycle



Carnot Theorem : For different engines opperating between same temp limits, no engine has the efficiency greater than carnot engine or reversible engines.

ηC.E  (ηHE1 , ηHE2 ) ηHE1 

w Q1

ηHE2 

w' Q1'

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T2  ηma T1 © VISION ENGINEERING Publications

T1

T1 Q1

HE1

T1 Q’’1

He2

W

Q2

W’

Q’’1 Carnot cycle

W’’ (Engine)

Q2

T2

T2

Q’’2 T2



Reversed Carnot Cycle : (Refridgerator & Heat pump)

A)

Carnot Refridgerator :

(COP)Carnot Ref 

TL TH  TL

(COP)Carnot H.P 

TH TH  TL

(COP) H.P  L  (COP) ref T1

Source Q rej

Carnot Refrigerator

Winp Q abs T2

5°C

Q.1) A heat engine operates b/w temp. limits of 100°K & 50K. The heat supplied to engine is 100 KJ & heat rejected is 40 KJ. Is the heat engine possible.



η

60 Q  60%  100 W

Assume it as carnot engine.

ηmax  1 

50 T  50  1  2 100 T1

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As ηHE  ηmax Hence heat engine not possible. T 1=100°k

Source

100 kJ

H.E

w = 60kJ

40 kJ T2= 50° k

5°C

Properties of pure substance :

Saturated liquid line

CP critical point V

Saturated vapour line

L T

L+V

S Specific entropy

Liquid  Vapour 

Evaporation

Vapour  Liquid  Condensation Constant Pressure line CP P3 = C P2 = C P1 = C

Liquid L+V

T Undercooled or Subcooled region

TCP  374C

Superheated region

S

Critical temp. of water

Dryness Fraction (x) : It is the ratio of mass of vapour to the mass of total mixture. VISION ENGINEERING ACADEMY, PUNE

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mV x

mL

mV mV  mL

CP Dryness fraction lines T x= 1

0 x = 0 .1 0.2 x= x =

x = x= 0. 8 0.9

S

Types of Heat : 1)

Sensible Heat : The heat transter associated with temp. change is called as sensible heat. Q  m C P .ΔT

2)

Latent Heat : The heat transfer associated with phase change is called as latent heat. e.g. If temp. of 1 kg of water increasef form 35°C to 100° Sensible Heat (Q) = m CP C P ΔT = 1 × 4.187 × (100 – 35) CP Tsup

Ts

hf Latent Heat

Sensible

hfg

Tl

Se n

T

sib l

eH ea t

P= C

hfg

S

e.g latent heat : 100° –––––––– 100°C water ––––––– steam phase change Ts = saturation temp. Deg. of superheating = (Tsup – Ts) Tsup = Temp. off superheated vapour. Deg. of undercooling or subcooling = Ts – Ti VISION ENGINEERING ACADEMY, PUNE

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Ti = Temp. of liquid line

L+ V

hf

hg

hfg

L

V

h S

hfg = hg – hf h = hf + x. hfg enthalpy of any pt inside air = hf + x (hg – hf) 1)

h = hf + x. hfg

2)

u = uf + x. ufg

3)

s = sf + x.sfg

4)

v = vf + x. vfg

Mollier Diagram : The h – s diagram for pure substance is known as mollier diagram.

CP

P=C

h

P=C P= C

L Saturated liquid line

L+V

V

Saturated vapour line

S

Slope of constant pressure line  dh   T On (h  s) or mollier diagram  ds  p Triple Point : It is the point where all theree phases exists in equilibrium. TTP  0.01C  273.16k

Temp.of Triple point

Gibbs phase Rule : F+P=C+2 F = no. of deg. of freedom P = no. of phases C = no. of components (H2O = 1) F at the triple point = 0 F+P=C+2 F+3=1+2 F=0 VISION ENGINEERING ACADEMY, PUNE

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Q.1) Thermodynamic work is the product of a)

Two intensive properties

b)

Two extensive properties

c)

An intensive properties & change in extensive prop.

d)

An extensive prop. & change in intensive prop. W



P dv change

Int prop

Q.2) Which one of the following expressess the reversible W.D by the system b/w the states 1 & 2 2

2

2

b)   V dp

a)  P dv 1

c)   P dv

1

1

2

d)

 V dp 1

2

for on the system ans :   P dv 1

Note :

Zeroth law of T.D : Measurment of temp. is based on zeroth law of T.D If two body c° then those two bodies A & B are in thermal equilibrium with each other.

Q.3) Which one of the following is the extensive prop. ? a) Volume

b) Press.

c) Temp.

d) Density

Q.4) Match the following : A)

Volume

1) Path function

B)

Density

2) Intensive prop

C)

Pressure

3) Extensive prop

D)

Work

4) Point function

Codes : A

B

C

D

(a)

3

2

4

1

(b)

2

3

4

1

(c)

3

2

1

4

(d)

2

3

1

4

Q.5) For a closed system the diff. b/w heat added to the system & the work done by system is equal to change in a) Enthalpy Q.6)

 (δ

Q

b) Entropy

c) Temp.

d) Int. energy

 δ W )  0 becoz cyclic process

ΣδQ  Σδ W VISION ENGINEERING ACADEMY, PUNE

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Q.7) The change in int energy accuring in a closed system is equal to the heat transferred if the process occurs at. a)

Constant pressure

b) Constant volume

c)

Constant temp.

d) Constant Enthalphy

Q  W  ΔU Q  ΔU when W = 0 isochoric process Q.8) Consider the following statements : 1)

Ist law of T.D is law of conservation work

2)

PMM-I converts energy into equivalent work

3)

IInd low of T.D is law of consevation of energy & entropy

4)

A closed system does not exchange energy with it’s surrounding. Which of above statement correct a) 1 & 2

b) 2 & 4

c) 2, 3 & 4

d) 1, 2, 3

Q.9) Which one of the following is the steady how energy equation for a boiler. V12 V2  q  h2  2 2gz 2gz

a)

h1 

c)

V12 V22 h1   h2  2 2

b) W = (h2 – h1) + Q d) Q  (h 2  h1 )

V12 V22 h1   gz1  9  h 2   gz 2  w 2 2 | | for boiler

0 Assume K.E & P.E changes neglibible Q = (h2 – h1)

 10)

A heat engine gives o/p of 3kw when the input is 10 KW. Efficiency of engine will be

η

 11)

O/P 3   100 I/P 10

 30%

W Qs

A thermodynamic cycle consist of 4 process. The heat & work as follows. Q = + 30, – 10, – 20, + 5 W = +3, + 10, 8, 0 find the efficiency of cycle.

η Note :

Work done 15 1     100 (only Heat supplied Take only  ve terms) 35 7

The IInd law of T.D also called directional law or law of degradation of energy.

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Note : 1) Zeroth law : defines temperature (T) 2) I st law : Internal energy (V)

3) IInd law : Entropy (S) 

The efficiency of reversible engine (carnot engines operating b/w the temp. limits (t1 & t2) is maximum

12)

Variation of press & volume at constant temp. is co-related by a) Charles law

13)

b) Boyles law

c) Joules law

Match the pairs. List I

List II

A) Adiabatic

1) n  

B) Isothermal

CP 2) n  C

V

C) Constant press

3) n = 1

D) Constant volume

4) n = 0

Codes : A

B

C

D

(a)

2

3

4

1

(b)

2

4

3

1

(c)

3

2

1

4

(d)

2

3

1

4

PVr = C Note :

Charles law 1 / Gay Lussac Law

p α T (V  C) Charles law 2 / Note :

p α T (P  C)

Daltons law : O 2  Po2   N 2  PN2  Patm CO2  Pco2 

Note :

Avagadro’s law : Equal valumes of all the gases contains same no. of molecules

Joule  N.m

J/s 

N/m watt  s s

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V O2

Note :

V N molecule

N2

Universal Gas Constant ( R ) Ideal Gas equation = PV = NRT

R – charact gas constant

PV = N R T

PV = nM ×

n = no. of moles =

m M

R ×T M

PV  nR T

R = universal Gas constant = 8.314 R =M×R Joules law V = f (T) only

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CHAPTER 2 : HEAT TRANSFER ===================================================================================== Heat Boundary phenomena. Transfer occurs due to 1)

Temp. difference.

2)

Phase change (Latent Heat transfer) w system Surround Work(w)

Q

Boundary

Heat & work are boundary phenomenon or they are they energy in transit. –

Heat is defined as the energy in transit across the boundaries of the system due to temp. difference

–

It always flow from higher temp. medium to lower temp medium.

–

The amount of the heat transferred across the system can be determined using Ist law of T



Applications of Heat transfer : 1)

Heat exchanges

2)

Refridgeration Ducts

3)

Air conditioning systems

4)

IC engines,

5)

Motors, generators & Tranformers.

6)

Design of steam Generator, condensors & cooling towers

7)

Electronic systems like computers, TV

8)

To avoid creation of thermal stresses

Modes of Heat Transfer :

1)

1)

Conduction – Fourier’s law of H.C

2)

Convection – Newton’s law of cooling

3)

Radiation – Stefan Boltzman law

Conduction : Fourier’s law of H.C Heat conduction is the transfer of heat energy from one substance to another substance which are in physical constact with each other.

–

Heat is conducted in solids, liquids & Gases.

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–

In case of solids a) Metals : Conduction is due to the flow of free electrons. b) Non - metals : Conduction is due to the lattice vibrations. c) Liquids : Conduction is due to molecular momentum transfer. d) Gases : Conduction is due to in moleular collision rate. Fourie’s Law of Heat Conduction : The law states that the rate of Heat conduction (H.C) through a substance is directly proportional to 1)

Area normal to the direction of heat flow.

2)

Temperature Gradient in the direction of heat flow. T i > T0  dT   dx    T0 Q

Q

Ti

Ti > T0

A T0 x

Iron rod - more free electron. Q = Rate of heat conduction (j/s or watt) A = Area normal to the direction off heat flow (m²) (J/s or Watt).

dT  Kelvin   Temp. gradient   dx  m  K = Coefficent of thermal conductivity & it is the propertly of the materials.

 dt  Q   KA    dx  The – ve sign in the fouriers’s law indicates that temp reduces in the direction of heat flow.

 Watt  Thermal Conductivity (K) :    m.k  It is the ability of the material to conduct heat through it. –

The materials which have high value of thermal conductivity are called as conducting materials

e.g

 w  Silver (highest) = 416  ,  mk 

 w  Diamond - non metal = 2100    mk 

–

The materials which have low value of thermal conductivity are called as insulating materials.

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e.g. Asbestos, Cork, Glass, Rock wool, polysterene.

 w  K copper  386   , silver, copper, aluminium, iron, are conducting materials.  mk  –

In order to reduce the heat lossess we provide insulationn.

Application of Fourier’s Law : 1)

Heat conduction through a think wall :

Ti

k Q

x=0

T0 Q

KA(Ti  T0 ) L

x=L L

Assumpotion in fourier’s law : 1)

Heat flow is unidirectional

2)

The material is homogeneous & isotropic.

3)

The temp. gradient is constant throughout.

4)

There is no internal heat generation.

Analogy Between Heat Conduction & electrical system :

I

R

I I

V

V R

(A)

I = current flow V = Potential diffrence R = Electrical Resistance

Q Q 

KA (Ti  T0 ) L ( Ti  T0 )  L   KA   

(B)

I

is analogus to Q - Heat flow

V

is analogus to (Ti – T0) – temp. diffrence

R

 L  is analogus to    KA 

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Composite Walls : a)

Series Combination : k1

Ti

k1

Q

Ti T0 L1

L2

Q = Q1 = Q2

R1 

L1 K1A

R2 

L2 K2A

Req  R1  R 2  Q

Q

Q

Ti  T0  L1 L2  K A  K A  1 2 

 Imp

Ti  T0 Req.

Ti  T0  L1  K A  1 

Q2 

b)

L1 L  2  Im K1A K 2 A

T1  T0 k

Parallel combination : A1 K1

Q1 T0

Q

Ti

Q K2 A2

Q2 L

A2 > A1

R1 

L K1A1

R2 

L K 2A2

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1 1 1   Req R1 R 2 1 R  R2  1 Req R1 R 2 Req 

R1 R 2 R 1 +R 2

Q = Q1 + Q2

Ti  T0 Ti  T0  R1 R2

Q b)

Heat Conduction Through Long Hollow Cylinder :

r2

T0

Ti r

1

L

Q

Ti  T0  R thermal  L n (r2 /r1 )     2π kL 

(R thermal ) Hollow cylinder  c)

Ln (r2 /r1 ) 2π kL

Heat Conduction through Hollow Cylinder : K T0

Ti

r1 r2

A  4π r 2

 dT  Q   KA    dr  Q

Ti  T0 r2  r1 4π kr1 r2

R thermal 

r2  r1 4 π k r1 r2

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2)

Convection : Newton’s law of cooling.

–

It is the mode of heat transfer which takes place due to movement of the fluid adjacent to the solid surface.

–

Convection is classified into two types a)

Free convection :

–

Convection currents are set due to density due to which of buoyant force results & it causes the heated air. q Heated air

Convection currents

q Cold air

b)

Forced convection : Heated air

8

Convection currents

fan

Cold air

To improve the rate of convective heat transfer by the use of fans or blowers then such type of convection is called forced convection. Co-efficient of Convective Heat Transfer : (Film conductacnce) –

Denoted by ‘h’ Heated plate

δ

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It is defined as ratio of thermal conductivity of film to it’s thickness. Unit of h 

k

watt m² k

watt m.k

Newton’s Law of Cooling : States that rate of convective heat transfer is directly proportional to the. a)

Surface area

b)

Temp. diffrence b/w wall surface temp. & the fluid temp.

A T f Thermal condinctive resistance = 1 hA

Tw

Q α A (Tw  Tf ) Q  hA (Tw  Tf ) Q = Rate of convective H.T h = coeff. of convective H.T A = Surface area Tw = wall temp. Tf = fluid temp 

Overall Heat Transfer Coeffient (U) : e.g. Boiler  Conduction + Convection Convection Conduction Convection hi

Q

h0

T1 T1 T2

T0

R1

R2

R3

L h iA

L KA

L h0 A

L

Req = R1 + R2 + R3

Req 

1 L 1   h i A KA h 0A

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Q

A (Ti  T0 ) 1 L 1   h i A KA h 0A

Imp.

Q = UA (Ti – T0)

U

3)

1 1 L 1   h i k h0

Radiation : For conduction & convection  Required material medium.

–

Radiation is the mode of heat tranfer by the means of electromagnetic waves emitted in the wavelength band of 0.1 μ m to 100 μ m.

–

Radiation takes place through vaccum. Q  Qa  Qr  Qt

1

Qa Qr Q t   Q Q Q

1)

Coeff. of absorption (α) 

Qa Q

2)

Coeff. of Reflection (ρ) 

Qr Q

3)

Coeff. of Transmission Transmissibility (τ) 

Qt Q

 α ρ τ 1 Black Body : A black body is the body which absorbs entire radiation incident upon it e.g. Carbon black. Qa  Q

–

Black Body

α 1

Qr  Q t  0

ρ&τ  0

A black body is also a best emitter ar radiate. Opaque Body : Solids .

–

It is a body which does not transmit any radia τ0

αρ 1 White Body : A white body is the body which reflects the entire radiation. VISION ENGINEERING ACADEMY, PUNE

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Whit body is also known as transparent body or diathermanous body.

α τ  0 ρ 1 For Gases of & Glass : τ 1

αρ0 Emissive Power : The energy emitted by the surface per unit & per unit area is known as emissive power.

 Watt  (E) unit     m²  Emissivity (E) : It is the ratio of emissive power of any surface to emissive power of body at the same temp. Eb

E A Normal body

Black body

100°C

100°C

Stefan Boltzman Law : (Black body) States that the emissive power of black body (Eb) is directly proportional to the forth power of the absolute temp. (T) Eb α (T)4

T  k

Eb  σ AT 4

for black body

σ – Stefan Boltzman constant

A – Surface Area –

For Grey body (body other than black body) E  6 AT 4 Conduction – (k) – (w/mk) Convection – (h) – (w/m² k) Radiation – (6) – (w/m² k 4)

σ  5.67  108 

W m², k 4

Imp.

Heat Flux (q) = q

Q A

 (w/m²)

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1)

Conduction



 dT  Q   KA    dx  Q  dT   K   A  dx   dT  q  K    dx 

2)

Convection



Q = hA (Tw – Tf). q = h (Tw – Tf)

3)

Radiation



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Power Plant Engineering ========================================================================================= 

Electricity or power – is the only form of energy which is easy to produce, easy to use, easy to transport & easy to control.

–



Energy sources are classified into two types. a)

Conventional energy resources – Coal, Oil, Natural gas, Water, Nucler energy.

b)

Non-conventional – Solar, Wind, Tidal, Giothermal biogas.

Types of power plants : 1)

Thermal or steam power plant

2)

Nuclear power plant

3)

Hydro-electric power plant

4)

Solar-Wind Hybrid power plant

5)

Gas Turbine power plant

6)

Geothermal power plant

1)

Thermal or Steam Power Plant :

–

Steam p.p or thermal pp are used in which the chemical energy of fuel is used to convert water into high pressure & high temp. steam inn the boiler.

–

This high temp. & high pressure steam is used in a turbine to produce mechanical power which is finally converted into electrical energy by use of an alternate.

_

–

The components of steam power plant are 1)

Boiler

2)

Steam Turbine

3)

Condensor

4)

Feed pump or pump

Works on Rankine Cycle.

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Air preheater

Surrounding Air blower

Feed water Economiser Superheater

Steam turbine

Water tubes

Stream mains

ws

Generator

Heated water Condensate

Cooling tower Cool air

Condensate extraction pump

Fuel gas

Cooling water

Furnance Feed fump Boiler

Heated air to atmosphere

Condenser water circulating pump

Hot well

Functions of components of steam pp : 1)

Air Blower : The function of air blower is to draw the surrounding air needed for the pre-heater.

2)

Air Pre - heater : Is the divice which will heat the air the atmosphere through the chimney.

–

This heated air is then supplied to furnace.

3)

Furnace : The heated air from air pre-heater supplied to the furnace where fuel is burnt.

–

The mixture of heated air & products of combustion of the fuel is called flue gases.

4)

Economiser : The feed water before supplied to the water tubes is heated by flue gases inside the economiser.

–

It reduces energy needed for formation of steam & improves the thermal efficiency of the plant.

5)

Steam Turbine & Generator :

–

High pressure high temp. superheated steam from the boiler exponds in the turbine & produces mechanical work.

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This work is utilized to drive the generator which converts mechanical energy into electrical energy. 6)

Condensor :

–

The steam from the steam turbine is exhausted to the condensor where steam is condensed by rejecting heat to the cold water from coooling tower.

7)

Feed Pump :

–

The condensate collected in the well along with the make-up water is fed back to the boiler. Advantages : 1)

Fuel used is cheaper.

2)

Space required is less.

Disadvantages :

2)

1)

Operation & maintenance cost is high

2)

Large amount of water is required

3)

Pollution causes health problem

4)

Part load efficiency is less.

Nuclear Power Plant : Nuclear fusion - Sun nuclear fission - chain reaction

–

In nuclear PP, nuclear fission reaction takes place.

–

The nuclear fuels used are.

–

a)

Uranium (U235) Natural

b)

Thorium

The energy released by the fission of 1 kg of uranium 235 is equal to the heat energy obtained by buring 4500 tones of coal 2200 tones of oil. U 235  01 n  Ba  kr  3 01 n  Energy.   Barium kerpton

E  mc²  3  108 m/s VISION ENGINEERING ACADEMY, PUNE

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Components of Nuclear P.P : 1)

Nuclear Reactor :

–

The energy is released by bambarding slow moving neutrons on the atom of U235 by the nuclear fission reaction inside the nuclear reactor.

–

The energy released by this reaction is taken away by the primary coolant.

2)

Moderator :

–

The nuclear fission reaction produces fast moving neutrons.

–

This neutrons are slowed down by the use of moderator. e.g. Carbon, heavy water, Graphite & Beryllium.

–

Moderators reduce the K.E or speed of neutrons.

3)

Control Rods :

–

Control rods are used to control nuclear chain require

–

Control rods absorb the neutrons. Control rod e.g. cadmium, (cd), Birab (B), Indian (In)

4)

External shield / Biological shield : To protect against neutron and the gamma eays.

5)

Heat Exchanger :

–

In this the heat absorbsed by the primary coolant is transferred to the water.

–

This water is converted into high press high temp. steam.

–

The primary coolant = CO2, Halium, liquid metals sodium & potassium.

–

Heat exchanger acts like a boiler of stem PP. Advantages : 1)

Large amount of energy is relased by small amount off fuel.

2)

It does not cause air pollution.

3)

Less space is required.

4)

Performance is high.

Disadvantages :

3)

1)

Skilled manpower required.

2)

Capital cost is high

3)

High degree of safety is required.

Hydro-Electric Power Plant : 1)

Reservoir : A reservoir is provided to store water during rainy r - season & supply the same water during dry season.

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–

The water from reservoir is used to to run the turbine. Reservoir

dam Gate Penstock Anchors Transformer room

Transformer room Power house Generator

Hydraulic line Tail water level

2)

Dam :

–

A dam is a stucture of considerable height built across the river. It’s function is to

3)

Trash Rack : Made from steel bars is provided to prevent entry of debris into the intakes from the dam.

4)

Gate : Is provided for controlling the flow of water from the resevoir to the hydraulic turbine to the penstock.

5)

Surge Tank : The function of surge tank is to protect the penstock due to sudden variation of velocity of water.

6)

Penstock : Is the pipe which carries water from reservoir to the turbine. It is the large pipe of 1/2 m in dia made up of concrate.

7)

Anchors : These are the concrete blocks to support the penstock.

8)

Hydraulic Turbine : Air used to convert K.E of water into mechanical energy.

9)

Tail Race : A tail race is reservoir where the water is discharged from the turbine to the river.

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Principal of operation : In hydro-electric PP. the P.E of water is utilised to move the hydraulic turbine. Which in turn runs an electric generator. to convert mechanical energy into electrical energy. 4)

Solar - Wind Hybrid Power Plant : A]

Solar Power Plant : Hot fluid

Sun Rays

Superheated steam Heat fxchanger

Solar collector

Generator Steam T

Steam Generator Condensor water pump

Solar Thermal panel

–

Cold fluid

Solar concentrating type of solar collector are used to produce high pressure high temp. superheated steam.

–

This steam is used in conventional steam PP.

Photovoltaic Cells : Avoid overcharging p.v cells Array

Charge controller

DC load

Battery (Energy storage)

Inverter

Power Transformer

AC load

D.C

1)

PV cells :

–

Solar PV cells are used to convert the solar energy directly into electrical energy. (DC current)

–

The power which is generated can directly be used as DC power or AC power by using an inverter. PV panel made from semiconductor i.e. silicon sandwich

2)

Battery : The excess DC power produced by the PV cells is stored in the battery through the

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charge control. 3)

Charge controller : Voltage regulator / charge regulator 1)

Avoid the battery from overcharging.

2)

It does not allow current to flow back the PV cells therefore it avoids dam age to PV cells.

4)

Inverter : DC power is converted into AC power using inverter.

5)

Power Transformer : Is used either to increase the voltage (step-up) or to decrease the voltage (stepdown)

–

Generally step-up transformers are used.

B]

Wind Energy PP : Winds are produced on earth surface due to follwing reason. a)

Heating of earth surface due to obsorption of solar radiation.

b)

Rotation of earth & it’s motion around a sun

Velocity sensor Wind

Brakes

Gear Box

Shaft Generator

Airfoil shape

Slow

+

Fast +

Tower Gear

Rotor with Bodies

Pinion

Gear Ratio = 1 : 90

Principle of operation : The KE of the wind is converrted by the wind mills to produce mechanical energy which in turn is converted into electrical power by means of a generator. Gear Box : is used to achieve high speed ratio. Brakes : During excessive wind condition brakes are used. Velocity sensor : Measure the wind speed & direction The electricirty generated is transfereed through the cables at the base where stepup transformer is located. VISION ENGINEERING ACADEMY, PUNE

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Solar - Wind Hybrid PP : Wind turbine Generrator AC load AC to DC Wind

Generator

Gear box

Rectifier

Inverter Solar Radiation

PV cells Array

AC load

Charge Controller DC load

Consumer control device

To consumer Battery

–

Rectifier is used to convert AC to DC

–

A system using combination of wind power & solar power is called as solar wind hybrid power system.

–

In most of locations the wind blows when the sun is not shinning or wind velocities are low when sun is shinning.

–

During the wind period the wind turbine generates AC power. It can be used directly as AC load,

–

The excess AC power is converted into DC by rectifier & stored in the batteries.

–

During favourable condition of sunshine the solar PV cells converts the solar radiation into DC power. It is also stored in the battery

–

This DC power stored in the battery is converted into AC by an invertor.

–

The solar wind hybrid system ensures continuous power supplyy & are used at remote location where transmission lines are not available.

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Machine Elements ================================================================================ Types :

1)

1)

Power Transmission shafts

2)

Axle

3)

Key

4)

Coupling

5)

Bush & Ball bearing

6)

Flywheels

7)

Governers

Machine : A device consisting of various m/c elements arrange together so as to perform the perscribed task to satisfy the human needs.



Types of M/c elements : 1)

Holding type elements e.g.

2)

Supporting type element

3)

Power transmitting elements. 1)

Holding type element e.g Nuts, bolts, rivets, cotters, keys.

2)

Supporting type element e.g Bearing, Axles, Brackets, frames

3)

Power transmitting elements e,g, shafts, gears, pulleys & belts, chain drives.

1)

Shaft : Shaft is rotating memb. circular in c/s used to transmit power or motion. In order to transmit power from one shaft to another shaft various memb. like gears pulleys are mounted on it with the help of key.

Types : 1)

Transmission shaft : The shaft which is used to transmit the power b/w the source & machine absorbing the power is called transmission shaft.

–

Transmission shafts are subjected to torque, Bending moment & axial force a)

Line Shaft : Line shaft is the transmission shaft which is directly diriven by the prime mover or power source.

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T

G Line shaft

b)

Counter shaft : Is the secondary shaft which is drriven by main shaft through belt, chain or gear drive. T Main

G Counter

2)

Machine shaft : Is the short rotating shaft which forms integral part of the m/c itself M/c shaft

Spindle Crank shaft

M/c shaft are also subjected to torque, BM & axial force. e.g. Spindle, crank shaft. 2)

Axles : It is a non-rotating M/c element which is used to support rotating M/c element like wheels, pulley etc.

–

An axle does not transmit torque.

–

It is subjected to B.M & axial force only. e.g. Front axle of car, Wheel axle of motor - cycle, Shaft Materials :

3)

1)

Plain carbon steel - 40C8, 45C8, 55 C8

2)

Alloy steel – 40 cr 

Keys : A key is M/c element used on the shaft to secure the rotating elements like gears, pullye & prevent the relative motion b/w two. Keyway : It is a slot or recess in a shaft & the hub of ratating element



Functions of keys : 1)

To prevent the relative motion b/w shaft & rotating element like gear pully etc.



Materials used for key : 1)

Plain carbon steel

2)

Alloy steel

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Generally, the material used for key has less strength than the shaft material to ensure that there is failure of key before the failure of shaft. 

Classification of keys : Rectangular key Sunk keys Square key Saddle key Parallel key Tangent key Keys

Gib head key Kneeding key Feather key Splines Woodruff key Round key

1)

Sunk key : are provided half in the keyway of the shaft & half in the keyway of the hub of the rotating element.

Key

w h

d-dia. of shaft

d

shaft Pulley

a)

Reactangular key :

w

d 4

&

h

2 w 3

Imp.

Applications : 1)

Mounting of flanges

2)

Pulleys & gears

b)

Square key :

wh

d 4

Imp.

Applications : Same as above c)

Parallel key : a parallel key is may be rectangular or square c/s & it is taperless

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Applications : Used in the Gear box. d)

Gib headed key :

It is a rectangular key with a head at one end know as Gib head. Gib head is provided to facilite removal of key. Applications : Used for mounting rotating element like Flywheels, pulleys, gears. e)

Feather key : Is a special type of parallel which is attached either to the shaft or hub off rotating element.

–

The feather key prevents relative rotary motion but permit relative axial motion.

Applications : Used in cluthes & gear shifting devices. f)

Woodruff key :

–

It is a segment from the cylindrrical disc.

–

It facilitates the easy removal of the rotating element from shaft.

–

Used for tapered shaft. Tapered shaft

Used in M/c tools & automobiles 2)

Saddle Keys :

–

It is a tapered key which completely fits in the keyway provided in the hub of rotating elements.

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a)

Hollow saddle key :

b)

Flat saddle key :

–

The torque is transmitted due to the friction b/w key & the shaft. Hence the torque transmiting capacity of saddle key is low.

–

Saddle keys are used for light duty applications.

3)

Tangent Keys : 90° shaft

Rotation element

–

Tangent keys consist of two tape rectangular keys placed 90° apart.

–

Each key withstand the torqu in one direction.

–

Tangent keys are used for heavy duty industiral application.

4)

Kennedy key : 90°

–

Kennedy key consist of the tappered square keys 90° apart.

–

Used in heavy duty industrial applications.

5)

Round keys & Taper pins : Round key

Rotating element shaft

–

Round key is a straight pin circular c/s. Used for low power drive.

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6)

Splines : Splines

shaft

Hub

–

Splines are the multiple keys which are made integral with the shaft.

–

Splines prevent relative rotary motion but permit relative axial motion b/w shaft & hub.

– 4)

Used in automobile gear box & M/c tool gear box.

Couplings : Is the mechanical element used to connect two shafts to a transmission system & transmit the torque form one shaft to the another shaft. Electric motor

m/c

e.g. Coupling 

Functions : 1)

It provides for the connection of shafts of two different units such as electric motor & M/c.

2) –

It reduces the transmission of vibrations & shocks b/w two connected units.

Types of coupling :

1)

Rigid coupling :

–

Rigid couplings are used to connect two shaft which are perfectly aligned.

–

This couplings are not capable of tolerating any misalignment b/w two shaft.

–

This couplings are not capable of absorbing shocks & vibrations.

–

They are simple & inexpansive.

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a)

Muff or sleeve coupling : sunk key

Driving shaft

–

Sleeve or muff

Driven shaft (m/c)

It consists of a sleeve or a hollow cylinder made of cast iron fitter over the ends of the shaft to be connected & keyed by means of sunk key.



Applications : Used to connect two line shafts.

b)

Split muff or clamp coupling : (Compression coupling)

–

Split muff coupling is the modification of muff coupling.

–

In this the sleeve is split into two half along a plane passing through the axis of the shaft.

–

The two halves of the sleeve are clamped by the bolts. (4, 8, 12, no. of bolts) sleeve 1 Bolts

Cutting of coupling into two halves

shaft to be connected Sleeve 2

Advantages : –

It is easy to assemble & disassemble. It can be easily removed without moving the shaft in the axial direction.

–

It has higher torque transmitting capacity than the muff coupling.



Applications : Used to connect two line shafts.

c)

Rigid Flange Coupling :

–

It consist of two flanges one keyed to the driving shaft & other to the driven shaft .

–

This helps to bring two shaft in line & maintain the alignment.

–

The two flanges are coupled together by means of bolts & nuts. (3, 4, 6 no. s)

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360  120 apart 3 –

The flanges are made from cast iron nor cast steel. Applications : Used to connect electric motor the pump or compressor.

2)

Flexible couplings :

–

Used to cnonnect two shafts having small amount of lateral and / or angular mis alignment.

–

This coupling are capable of shocks & vibrations.

a)

Bush pin types flexible of couplings :

–

It is the modified version of rigid flange coupling. Brass Bush Bush pin Brass Rubber damping property

Advantages :

–

1)

It can tolerate small amount of lateral or angular alignment.

2)

It has high torque transmitting capacity.

In this coupling a rubber bush & a brass bush is inserted b/w the bolts known as pins.

–

The bush helps in absorbing the shocks & vibrations & compensate for the mis alignment.

Applications : To connect diesel engine to the generator. b)

Oldhams coupling : d or (e)

–

It is used to connect the two shaft whose axes are parallel & are at some distance apart.

–

Oldham coupling can connect non-coaxial shafts Which are at some distance apart.

Applications : Used to connect two eccentric shafts. VISION ENGINEERING ACADEMY, PUNE

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c)

Universal Coupling or Hooke’s joint :

–

It is used to connect two non-parallel & intersecting axes shafts having small angle b/w two axes.

e

Applications : It is used b/w gear box shaft & the difference ential of automobiles (car, bus, truck) 5)

Bearings :

–

Bearing is the M/c element which locates the two M/c parts relative to each other & permits the relative motion b/w them while cars the load.

–

Due to the relative motion b/w two parts there is friction & wear. So in order to reduce friction & wear a lubricant is provided b/w two parts.

–

This lubricant reduces friction wear & carries away a heat. shaft

M/c

Motor

(Mineral oil as lubricant) sliding contact bearing



Point

Rolling bearing

Types of bearings : 1)

Sliding Contact Bearing :

–

The bearings in which the contacting ourfaces a sliding contact & are seperated by a films of lubricant are known as sliding contact bear.

2)

Rolling Contact Bearing : The bearing in which contacting surfaces has rolling contact are known as rolling contact bearing.

–

Also known as anti-friction bearing.

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Bearings

Rolling Contact Bearing

Sliding Contact Bearing

Guide Bearing (linear motion)

Journal Bearing

Thrust Bearing

Footstep or Pivot Bearing

Ball Bearing

Collar Bearing Single row deep grove ball bearing

Solid Journal Bearing

Bush Bearing

Roller Bearing

Double row deep grove ball bearing

Angular contact bearing

Trust ball bearing

1) Cylin Roller bending 2) Neele roller bearing 3) Taper roller bearing 4) Taper roller Thrust Bearing

Split Bearing

Applications : Guide ways of M/c tools, piston cylinder, cross-head of steam engine Except Guide bearing the relative motion b/w two parts in rotational. 

Jouranal Bearings : 1)

Solid journal bearing : oil hole Bearing

Shaft or journal

2)

Bush Bearing : oil hole Bearing

Bearing

–

Bush bearing is the improved version of solid journy bearing.

–

A hollow cylindrical part called bush is fitted in a hole of bearing block.

–

A bush is made up of soft material like brass, bronze, babbit (alloy of tin, antimony copper) & aluminium alloy.

–

The uush which is made up of softer material takes up the wear.

–

When the bush gets worn out it can be easily replaced. Replace

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Applications : Bush bearing are used when shaft speed is high & the shaft carries medium to high loacks. 

Ball Bearings :

–

A ball bearing consist of 4 parts. 1)

Outer race

2)

Inner race

3)

Rolling elements (Balls or rollers)

4)

Seperators or retainer

Outer race Seperator Inner Race

Balls or Rollers

Seperator

–

Ball bearings use the spherical balls as the rolling elements.

–

The contact b/w inner race & the ball or the outer race & the ball is a point contact.

a)

Outer Race : It is generally stationary & it is supported in a frame or casing.

b)

Inner Race : It is mounted on shaft which is generally rotating.

c)

Seperator or Retainer : The seperator seperates the rolling elements & spaces them evenly (at equal angle) around the periphery.

1)

Single Row deep groove ball bearing :

–

They have high radial load carring capacity & moderate axial or thrust load carring capacity.

2)

Double Row deep grove ball bearing :

–

They can carry heavy radial & heavy axial (thrust loads)

3)

Angular contact bearings :

–

Have very high axial (thrust) load carring capacity in one direction only.

4)

Thrust ball bearings : Thrust ball bearing are used to take pure axial or thrust load.

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Applications of Bearings : Sliding contact

Rolling contact

1) Marine engines

1) Industrial & automotive gearbox

2) Large size centrifugal pump

2) Electric motors

3) Large size conveyors

3) M/c tool spindle

4) Steam & gas turbines

4) Small size centrifugal pump 5) Automobile front & rear axles.

6)

Flywheels :

–

It is a device used to reduce the fluctuation speed during each cycle.

–

It is mounted on the shaft of the prime movers. (e.g. motor) Flywheel used to control flucturation of speed Governer maintain constant mean speed Used in punching machine

–

In some of machine like punching M/c reciprocating air compressor, 4 stroke diesel engine, 4 stroke petrol engine the torque is nott constant but fluctuating during the cycle.

–

The fluctuation of the torque causes fluction of speed. P 

2πNT 60

Hence flywheel is used to reduce this fluctuation of speed. –

Flywheel is a heavy rotating body which acts like a energy reservoir by the virtue of it’s mass moment of Inertia.

–

The flywheel stores rotational K.E during the period when supply of energy is more than the requirement of energy by the M/c. & it releases the energy during the period when the requirement of energy is more than the supply of energy.

–

When flywheel absorbs the energy it’s speed will increase & when it releases the energy it’s speed decreases.



Types of flywheel : 1)

Solid disk flyweel

2)

Rimmed flywheel

Solid disk

Applications : 1)

Electric motor driving punching M/c

2)

Rivetting M/c

3)

Shearing M/c pressure.

4)

4 stroke diesel engine driving the centrifugal pump Reciprocating compressor or stone crusher.

5)

4 stroke diesel engine driving the automobile.

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7)

Governers :

–

Governer is the device which is used to maintain consant speed of the engine within the prescribed limits over the long periods.

–

When load on engine increases it’s speed decrease in order to maintain the speed constant it is necessary to increase the supply of fuel to the engine.

–

When load on engine decreases, its speed increases. In order to maintain speed constant it is necessary to decreases the supply of fuel to the engine.

–

The qovernor automatically control supply of fuels to engine & there for it maintain constant meanspeed.



Types of Governers : a)

Centrifugal Governers :

b)

Inertial Governers :

a)

Centrifugal Governer :

–

Watt governer is the simplest type of centrifugal governer.

–

Centrifugal governer works on the principal of centrifugal force.

Applications : 1)

Constant speed IC engine

2)

Steam turbines

3)

Gas turbines

4)

Hydraulic turbines

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5. Engineering Materials And Design =========================================================================================== The selection of material for the M/c element is one of the imp steps in the process of M/c design. 

Mechanical properties of materials : 1)

Static strength : (At rest) It is the ability of material to resist the stress without failure when subjected to static loading.

2)

Fatigue strength : Is the ability of a material to resist the stress without failure when subjected to fatigue load. (cyclic, repitative load) Tensile Comp

3)

Elasticity : The property of material which enables it to regain it’s original shape after the removal of exit load.

4)

Plasticity : The ability of the material which enables it to retion the permanent deformation after the external load is removed is called plasticity.

5)

Ductility : The property of the material that enables it to be drawn out or elongated is called ductility. e.g. Mild steel, aluminium & copper

6)

Brittleness : Is the property opposite to ductility in which there is lack of deformation. e.g. cast iron σ  for Brittle material σ



7)

Resiliance : The capacity of a material to absorb energy within the elastic range is called resilience.

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After removal of load conly within elastic range According to Hook’s law.

=

σαE

σ E

σ E 

Resilience =

8)

Toughness :

σ² 2E

Total capacity of the material to abosorb the energy without fracture is called as toughness. e.g. Find toughness 9)

Hardness : Is the prop of material to resistane the penetration indentation or abrasion.

10)

Creep : Is the plastic deformation which occurs under a constant load over a long period of time. Creep becomes dominent at homologus temp.

Homologus temp(iron) 

1  1540 2

1   2  MP of material (melting pt) 

= 770° 

Classification of Engineering Materials :

Metals & Allys

Ferrous alloy

Composites

Non-ferraus metals & alloys

Particulate composite

Reinforces composite

Non metals : a)

Wood

b)

Glass

c)

Rubber

d)

Leather

e)

Asbestos

f)

Carbon

g)

Plastic

h)

Ceramics

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A)

Ferrous Alloys :

–

Ferrous alloys are those which have iron as their main constituent.

–

All the ferrous alloys are made by refining pig iron.

–

The commonly used ferrous alloys are a)

Cast irons : is a 4 elements alloy

1)

Iron

2)

Manganese

3)

Silicon

4)

Cast iron has excellent M/c ability. Excellent machinability is due to silicon cast iron Self lubricating  Graphite flakes Properties of cast iron – The presence of graphite provides excellent machinability, wear resistance & ability to damp vibrations.



Disadvantages : Cast iron is a brittle material. Hence poor tensile strength.







Application : 1)

M/c tool beds

2)

Columns

3)

Guide ways

4)

Ic engine cylinder blocks & cylinder heads

5)

Gears, pulleys, flywheels, couplings, bearing housing

Types of Cast Iron : 1)

Grey CI

2)

White CI

3)

Malleable CI

4)

Ductile or Nodular CI

Designation of CI : FG 150 FG 300 FG : Grey cast iron 150 – Ultimate tensile strength in N/mm² or Mpa



Alloy Cast Irons : (Ni, Cr, Mo, V, Si) Alloying elements 1)

Nickel  increase strength & wear resistance.

2)

Chromium  increase corrosion resistance & hardness.

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3)

Molybdenum   stiffness, hardness & impact resistance.

4)

Vanadium   Hardness, fatigue, tensile strength.

c)

Steel : 1)

Plain carbon steel  Iron + carbon

2)

Alloy steel

3)

High alloy steel

4)

Cast steels

1)

Plain carbon steels :

a)

Low carbon steel – % C < 0.3 % (Mild steels)

b)

Medium C. steel – 0.3 % < C < 0.6 %

c)

High C. steel – C > 0.6 %

Applications : 1)

Low carbon steels are used for automobile bol spindles, levers & light duty gears,

2)

Medium carbon steels are used for nuts & bol transmission shafts, connecting rods.

3) 2)

High carbon steels are used for coil springs leaf springs.

Alloy steels : Alloy steels are the iron carbon alloy that contain : 1)

Chromium  Improves hardness & corrosion resistance.

2)

Nickel  Improves toughnes & ductility strength.

3)

Silicon  Deoxidising Agent

4)

Tungsten  Hot hardness or means ever at high tem. steel maintains hardness.

5)

Vanadium  Inorive fatigue strength steel or hardenability.. Tool steels are generally tungsten based.

6) 

Mangenese  It is used as deoxidesing & desulphurising agent

Designation of Alloy steel : 1)

20Cr 18 Ni 2 20  Carbon % = 0.2 % C Cr18 18 % Chromium Ni 2  2% Nickel.

2)

40 Ni Cr 1 Mo 15 0.4 % C 1% Ni & 15% Mo 1% Cr

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3)

40 Cr 1





0.40 % C 1 % Cr 3)

High Alloy steels : Stainless steel The iron based alloys containing at least 12 % chromium are called stainless steel.

–

High alloy steels are classified into 3 types. 1)

12 to 14 % chromium e.g

1) 15 Cr 13 2) 22 Cr 13 S28 0.22%C 13%Cr 28% Sulphur

Used for springs, turbine blades & surgical instruments : 2)

–

% C > 16 % – e.g.

07

Cr

17

05

Cr

17

0.05%

17%

C

C

As the high alloy steel have good strength at high temp. Hence they are also called as high resistant steels.

4)

Cast steels : Designation :

Cs 640 ultimate tensile strength (N/mm²)

 Cast steel –

Cast steels are lighter with good ductility, tough ness, fatigue strength & good resistance to impact loading.

B)

Non - Ferrous Metals & Alloys : 1)

Copper Alloys : a)

Brass

b)

Bronze

a)

Brass : Copper + Zink (Cu + Zn)

b)

Bronze : Copper + tin (Cu + Sn) Types : 1)

Phosphor bronze :

Copper + Tin + phosphor (Cu + Su)

2)

Tin Bronze or Gun metal : 88% Cu, 10% Sn, 2% Zn

3)

Monel metal : 28% Cu, 68 % Nickel.

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2)

Babbits : Babbits are the alloys of lead & ting with small proportion of antimony & copper. Applications of Bubbits : Bearings are mode up of babbits.

3)

Aluminium Alloys : QAl = 2700 kg/m³ Ssteel = 8000 kg/m³

–

Aluminium alloys have low specific weight.

–

The density of aluminium is very low as compared to steel. this makes the parts made from aluminium are light in weight

–

Aluminium alloys has high thermal & electrical conductivity.

Applications : Aircrafts & ship building. 

Non - Metals : 1)

Wood Light in weight



Disadvantage : Low strength



Applications : Pattern making in casting 2)

Glass : Weak brittle material

3)

Rubber : It is an elstomer with a minimum extension of 200% when sub jected to tensile load.

Types of Rubber : a)

Synthertic Rubber :

b)

Natural Rubber :

Appliction : Vehicle tyres, vehicle tubes are made from natural rubbers. Synthetic Rubber : Conveyor, V-belts are made from synthetic rubber c)

Leather :

4)

Asbestos : Asbestos is used for lagging are the steam pipe & steam boiler.

5)

Carbon : It gives low frictional lossess & wear rates.

6)

Plastic : Types : a)

Thermoplastics : The thermoplastic do not under any chemical change or do not become hard with the application of heat & pressure. e.g. Celluloid, polyamide, PVC tetra fluoro ethyli (PTEE)

b)

Thermosetting plastic : If first soften the heat bulas additional heat & press it become hard by process of polymerisation. e.g. Epoxy, phenyl - formaldehyde

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7)

Ceramics : are the inorganic & non-metallis materials which are processed & used at a high temperatures.

–

Ceramics have high melting point & they retain their strength at high temp. also

Application : 1)

Cutting tools

2)

Abrasives

Composites : –

Composites are made by combining two or more diff materials mechanically.

–

The components of composite do not form an alloy but they maintain their identities even after the composite is formed.





Types : 1)

Reinforced composite

2)

Particulate composite

Criteria for selection of materials : 1)

Availability of material

2)

Cost of material

3)

Manfacturing considerations

4)

Material properties



Design Considerations :



Step in the design process : 1)

Definition of problem : A problem is defined given all the input & output parameter & constrain.

2)

Synthesis : Synthesis is the process of select or creating mechanism for M/c.

3)

Analysis of forces : Draw the F.B.D of easy element of M/c & find out the forces inclyed moment & the torque acting on each element.

4)

Selection of material :

5)

Determination of mode of failure :

6)

Determination of mode of failure :

7)

Determination of diamension :

8)

Modification of diamensions : Modify the diamension on the higher side if reqd.

9)

Preparation of drawings : Prepare the drawing of each element with min. two views showing the following details. 1)

Diamension

2)

Dimensional tolerance

3)

Surface finish

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6. Mechanisms ================================================================================== 1)

Link : Each part of the M/c which moves relative to some other part is called a link.

–

A link should not be a rigid body but it should be a resistant body.



Resistant Body : A resistant body is a body which is capable of transmitting reqd. forces with negligible deformation.



Kinematic pair : If the two links or element of a M/c have relative motion b/w them which is either completely constrained or successfully constrained then the pair is known as kinematic pair. Completely Constrained

Incompletely Constrained

Completely Constrained

Incompletely Constrained

Only one motion possible Successfully constrained

Two motion possible

Only one motion possible

Two motions possible

Successfully constrained

Collar

Only sliding motion allowed rotation is restricted. 

Types of kinematic pairs : a)

Turning pair : Two elements of a pair are in such a manner that one can only revolve about the fixed axis link.

b)

Sliding pair : The two elements of a pair have sliding motion relative to another.

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Four bar chain mechanism : 3 l 1

Grashof law p 3

s

4 q

1)

Crank - It is the M/c element or purt of m/c which will make a complete 360° rotation.

2)

Lever or rocker - Is the part of M/c which will partially rotate or which will oscillate.

3)

Inversions : Inversions are obtained by fixing the diff. links in kinematic chain. If n = no of links in a mechanisms then, No. of inversions = n 3 = length of the shortest link.

 = length of the longest link p & q are the lengths of the other two links. (S + )  (P  q) (S + )  (P  q)



(S + )  (P  q)

 Two links will make 360° rotation

One link will make 360° rotation

3 2



4

Inversions of 4 bar chain mechanisms : 1)

Double crank mechanisms 3 2

4

Link 2 & 4 are 360° rotating crank e.g. coupled wheels of locomotive (train) 2)

Crank & leves mechanisms : e.g. Beam engine Lever

Piston 3 2 Crank

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–

Beam engine is used to convert the rotary motion of crank into the reciprocating motion of piston.

3)

Ackerman steering Gear Mechanism : or Double lever Mechanism : 3 4

2

1

In a 4 bar chain mechanism there are 4 turning pairs mechanisms. 

Single Slider Crank Chain : In this 1 sliding pair & 3 turning pairs e.g. Ic engine, Reciprocating air compressor.

2

3 4

1

A single slider crank is used to convert the rotary motion into the reciprocating motion & vice - versa. 

Inversions of single slider crack chain : 1)

First Inversion : Ic engine, Reciprocating Air compressor.

2)

Second Inversion : Whitworth quick return mechanism

3)

Third Inversion : Crank & slotted lever mechanism (quick return)

4)

Forth Inversion : Hand pump.



Intermittent Motion Mechanism : The intermittent motion mechanism are used converting continuous motion into intermittent motion. 1)

Geneva Mechanism

2)

Ratchet paul Mechanism

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1)

Geneva Mechanism : Geneva mechanism is used for converting constant rotary motion into intermittent indexing motion. When make complete rotation It will rotate the small angle

During one rotation of the driving crank the geneva wheel is indexed through

 360    degress.  n  Where n = no. of oradial slots in Geneva wheel. 2)

Ratchet Pawl Mechanism : This mechanism is used for converting the oscillating or reciprocating motion of the driving arm into the intermittent rotary motion of the diriven ratchet. Oscillating motion of driving arm

Intermittent rotary motion of ratchet

Locking pawl

Driven Ratchet

Driving Rtched Driving arm



Locking pawl : The locking pawl prevents the ratchet from rotating in reverse direction.



Application of Ratchet & pawl Mechanism : 1)

Counting devices

2)

Clock works

3)

Lifting jacks

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7. Power Transmission Devices ======================================================================================== 

a)

Types of power Transmission Devices : a)

Belt drive

b)

Chain drive

c)

Gear drive

Belt Drives : Belt drives are used to transmit the power from one shaft to another which are at considerable distance apart. Motor

Driving shaft

Electric Machine Driving shaft

–

The power is transmitted from the driving pulley to the driven pulley through the belt because of the friction b/w belt & pulley surface constant velocity ratio can not achieved due to small precentage of slip.

–

Belt drive is not a positive driven since a constant velocity ratio can not achieved due to small percentage of slip. Driven shaft Belt

Driving shaft

Driven pulley (D.N)

Driving pulley (d.n)

In clocks or wathces - Gear Drives d.D = dia. of the driving & driven shaft resp. n.N - speed of the driving & driven pulley resp in rpm. Speed Ratio :

i

D n  d N

If the k. of belt is given then,

i

Dt dt

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Types of Belts : 1)

Flat belts

2)

V - belts

3)

Timing belts

4)

Circular belts or ropes.

1)

Flat Belt : (Rectangular in c/s)

–

Crowned pulleys are used to avoid sliping of belt (to avoid the coming off of the belt)

–

Pulley with proper crowning.

2)

V – betts :

–

V – belts are trapezoidal in c/s.

–

In V – belt drives pulley are provided with a groove such pulleys are called groove pulley or sheves.

–

In V - belts power is transmitted by the wedding action.

3)

Timing belts :

–

The timing belt or tooth belt transmit power by means of teeth rather than hence there is no slip.

4)

Circular belt : are circular in c/s

Ropes



Materials of belt : Leather, Fabric, Rubber, polyester or polyamide.



Types of Flat Belt drives :

a)

Open Belt Drives :

In open drives pulleys are rotated in same drives. VISION ENGINEERING ACADEMY, PUNE

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b)

Crossed Belt Drives : Pulleys rotated in opposite dirives.

+ c)

+

Multiple Belt Drive :

Multiple Belt

Driven pulley

Driving pulley



Advantages of Belt drives :

–

Belt drives can be used for long center distances.

–

Belts are flexiable & have capacity to absorb shocks & vibrations.

–

No lubrication reqd. in belt drives.



Limitations :

–

It is not a positive drive hence can not be used in application where a constant speed ratio is required.

–

Chain Drive : e.g. bicycle

–

A chain drive consist of endless chain running around two pocket wheels chain drive needs lubrication for effective functioning. Applications : 1)

Bicycles

2)

Motor cycles

3)

Agricultural machinary

4)

Rolling mills

5)

Conveyors

Advantages of chain drives : A chain drives is a positive drive VISION ENGINEERING ACADEMY, PUNE

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Limitions : Need to provide lubrications. Power transmitting capacity  Gear drive > Chain Drive > Belt Drive Power transmitting = V belts > Flat belts. c)

Gear Drives :

–

Gear can be defined as the mechanical elements used for transmitting power & rotary motion from one shaft to another shaft by means of progressive cangagement of teeth. dg, zg, ng dp, zp, np Gear

+

pinion

+

dg. dp = dia. of Gear & pinon zg. zp = No. of teeth of Gear & pinion. ng. np = Speed in (rpm) of gear & pinion.

Gear or Ratio

Speed Ratio



Types of Gears :

A]

Parallel Axes Gears :

(G) 

dg np zg   dp ng zp

Two shafts whose axis are parallel. Parallel axis gears are used to connect or transmit the power from one shaft to another shaft whoese axes are parallel. –

Spur Gears

–

Helical Gears

–

Double helical Gears or Herringbone Gear

Spur Gear : The teeth are cut parallel to the axis of the gear. Speed Ratio (6 : 1) Efficiency – 96 – 99% Helical Gear : The teeth are inclined at an angle to the axis of the gear. Speed Ratio – 6 : 1 Efficiency – 96 – 99 % Double Helical Gear : It consist of two identical helical gears because the net axial thrust developed by the double helical gear will be zero. VISION ENGINEERING ACADEMY, PUNE

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B]

Intersecting axes Gears : Two intersecting axes shafts are connected by gears known as the bevelled gears. Bevel gear is a frustum of a cone having a shaft angle of 90°

C]

Non - intersecting & perpendicular axes Gear : Two non - intersecting & 1er axes shafts are by a worm & a worm gear. –

Speed Ratio = 70 : 1

–

Efficiency = 45 – 50 %

Hypoid bevel Gears Skew bevel Gears Crossed Helical Gears D]

Non - intersecting & non - parallel axes Gears : e.g

Crossed helical Gear or Spiral Gear.

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8. Clutches & Brakes =========================================================================================== 

Clutch : A clutch is a mechanical device which is used to connect or to disconnect the driving shaft from driven shaft at the wheel of the operator. Driving shaft Engine clutch

Gear Box Driven shaft

–

A clutch is mounted b/w the driving shaft & the driven shaft.

–

In automobiles in order to change the gears or to temporarily stop the vehicle the requirement is that the driven shaft should stop but the engine should continue to run. This is achieved by means of clutch.



Types of clutches : 1)

Positive clutch : Jaws

Driving shaft

–

Helical compression spring

Driven shaft

Jaw clutch is a simplest type of positive clutch which permits one shaft to drive the another shaft through direct contact of interlocking jaws.

–

Due to the helical compression spring the clutch is normally in engaged condition.

–

Positive clutches do not slip.

Disadvantages of positive clutches : –

Positive clutches can not be engaged at high speed.

–

Engagement & disengagement of + ve clutches is difficult

Applications :

2)

1)

M/c tools

2)

Power presses

3)

Punches

Friction Clutches :

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–

In a friction clutch two contacting surfaces are pressed against each other.

–

The frictional force b/w two contacting surfaces is responsible for transmitting torque. Driving plate

Driven plate Helical comp spring

Driving shaft Driven shaft

Friction lining

–

The friction lining is provided on the driven plate.

–

The axial force applied by heical comp spring holds the two plates together.

–

Friction clutch is not + ve clutch & Hence slip can occurs.

Types : 1)

Plate or disk clutches : Friction clutches

Plate or disk clutch

Single plate clutches e.g. Trick, bus kars

Reqd. large radial space

Cone clutch e.g. Mixers Grinders

Centrifugal clutch e.g. scooters mopeds Works on centrifugal action

Multi plate (wet) clutches e.g. Motorcycles

Reqd. small radial space Requires lubrications



Brakes : A brake is a mechanical device which is used slow down or to completely stop the motion a moving system such as M/c, vehicle or a rotating drum by applying an artificial friction resistance. Types : 1)

Block or shoe Brake : Used in trains, Tram cars

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2)

Internal Expanding shoe brake : Used in Trucks, buses automobile vehicles, cars motorcycles & scooters.

3)

Disk Brakes : Because of excellent control of disk brake they are used in motor cycles & racing cars.

4)

Band Brake : Band brakes are used in material handling equipents.

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9. Manufacturing Processes ================================================================================== Manufacturing process is the process of converting raw materials into finished product using machine.

Raw material Iron Block 

1)

Circular shaft

Machine or mfg. process

Finished product

Classification of Manufacturing Process : 1)

Casting

2)

Metal forming or deformation

3)

Machining or metal cutting

4)

Surface finishing

5)

Sheet metal working

6)

Metal joining process

Casting : A casting is the process in which the mollen liquid metal is allowed to solidify in a predefined mould cavity. Pouring basin

Riser

............................. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Extra molten metal ............................. spreue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cope ............................. ............................. moulding .............................

sand

Runner

drag

Pattern : It is the replica of the final casting to be produced. 

Pattern material : 1)

Wood

2)

Metals like aluminium, white metals

3)

Plastic like pvc, polystyrene, Thermocole, foam.

–

If plastic is used as a pattern material then casting process is called full moulding.

–

If wax is used as pattern material then casting process is called investment casting.

–

If plaster of paris (POP) is used as a pattern material, then casting process is called plaster moulding.

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Riser : To compensate for solid shrinkage extra molten liquid metal is provided through the riser.







Advantages of Casting : 1)

Large sized objects (1500-200 tonnes) can be manufactured by casting only.

2)

Complex shape of the object can be produced.

3)

Both ductile as well as brittle materials can be easily produced by casting.

Limitation of Casting : 1)

The accuracy & surface finish of casting is very poor.

2)

There is a possibility of casting defects. Blow holes

3)

Time consuming process.

Application of casting : 1)

Automobiles : Engine blocks Cylinder block Piston Gear box housing

2)

Turbine :

3)

Piping : Hollow cylindrical water pipes.

4)

Machine tool : M/c tool bed.



Cores are used to produce hollow cavities in the casting. The cores are supported inside mould cavity with the help of core point.



Classification of casting process : Expendable casting : Sand casting Full moulding Investment casting Permanent moulding : Centrifugal casting Die casting Slush casting Continuous casting

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Expendable Pattern Casting : a)

Sand casting : The casting process in which casting are made using sand mould is known as sand casting process.

–

Wood is generally used as a pattern material in sand casting.

–

Sand casting account for 75 – 80 % of total casting products.

b)

Investment Casting :

–

Pattern material is wax.

Pattern Tree dipped

Ceramic slurry (High mp)

–

It is used for the casting of high melting pt alloys.

–

It is known as lost wax process.

Application :

2)

–

Gas turbine blades

–

Gold ornaments

–

Medical implants

Permanent Moulding : a)

Centrifugal Casting : fc = mrw² Mollen liquid mejal

at high rpm

Metallic die

–

In centrifugal casting permanent mould is used called as die.

–

It works on the principal of centrifugal force. Fc = mrw²

–

High density pure metal will be subjected to more centrifugal force & will get solidify at the outer surface away from centre.

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–

Low density impurities will be collected at the center.

Application : –

Cast iron pipes

–

Hollow cylindrical & symmetrical pipes

–

Hollow propeller shafts

–

Gun barrels

b)

Die Casting : 1)

Gravity die casting – Aluminium alloy & pistons

2)

Hot chamber die casting

Hydraulic cylinder Fixed die

Movable die

–

In gravity die casting the liquid molten metal enter into die by means of gravity force.

–

In hot chamber die casting, complex shapes of the objects can be produced since the molten liquid metal is forced the use of hydraulic cylinder. e.g. carburettors

c)

Slush Casting : Thin casting

Hollow

–

Slush casting is used to produce thin casting & hollow thin casting.

Application :

\

–

Decarative items

–

Statues

–

Thin ornaments

–

Lamp shades

d)

Continuous Casting : To produce long length metallic objects continuous casting is used.

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2)

Metal Joining or Welding :

–

Welding is the process of joining two metallic part together by heating them to a plastic state with or without application of pressure & with or without application of filler material.

–

Welding Process needs 3 input elements : 1)

Heat : The heat reqd. for fusing the two parts is obtained from a)

Electric energy

b)

Combustion of Gases (Acetylene, H2)

c)

Chemical reaction (Thermit)

2)

Application of pressure

3)

Filler material

Applications of Welding :



1)

Fabrication of bridges

–

Electric tower, transmission tower

2)

Two wheeler & 4 wheeler automobile bodies

3)

Ship building & Aircrafts

4)

Manufacturing of boilers, pressure vessels.

Types of Welding : A)

Pressure Welding :

–

In pressure welding the two metal parts to be joined are heated to a plastic state & forced together by an external pressure.

–

In this does not reqd. filler material Pressure Welding

Force welding

1

a)

Resistance welding

Thermit welding

2

Forge welding is the press weding process in which the heating is done in black smith shawl by using coal. The ext. press. on the parts to be joined is applied by hammering.

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b) Resistance Welding

Spot welding

Seam welding

Projection welding

R Electrode

H = I² Rt

Spot welding +

R Roller electrodes

–

+

Seam welding

Projection welding

Resist welding is the press. welding process in which the heating is done due to resistance of metal parts for the flow of electric current b/w the two electrodes.

–

The external press. is applied by two electrodes.

–

In resist welding the amount of heat generated is given by, H = I² RT



Applications of Resist. welding :

–

Manufacturing automobile bodies (8000 – 10,000 spot welds)

–

Ship building & Aircrafts

c)

Thermit welding :

–

Thermit is the mixture of iron & aluminium.

–

Thermit is generated due to chemical reaction.

Applications : –

Railway Rotes

–

Large size broken casting

B)

Non-pressure Welding :

–

The two metals parts to be joined are heated to a plastic state & allowed to solidify to make a joint without application of external pressure. a)

Electric Arc Welding :

–

It is non - pressure welding in which the heating is done due to electric arcs between the electrode & the work piece.

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–

Filler material is used in this welding.

1)

TIG : Tungsten Inert Gas Welding :

–

In TIG welding the heating is done due to the electric are b/w non consumable tungsten electrode & workpiece.

2)

MIG : Non - pressure electric are welding in which heating is done due to electric arc b/w a consumable metal electrode & workpiece.

–

The filler material is provided by electrode itself

3)

SMAW : Non - press electric arc welding process which heating is done due to electric arc b/w flux coated consumable electrode & a workpiece.

b)

Gas Welding : If Acetylene – Oxy - acetylene Gas welding If hydrogen – Oxy - hydrogen Gas welding



Soldering & Brazing : (Metal joining) Lead + Tin

Copper + Zinc (Aluminium silver)

(solder)

(Spelter)

Soldering - is the process : of joining two workpieces made of similar or dissimi lar materials by beating them to a temp. below 450°C. –

The filler material (solder) is an alloy of lead & tin. Brazing - is the process of joining two workpieces made of similar or dissimilar materials by heating them to a temp. above 450°C below the metting pt. temp of workpiece.

–

Filler material (spelter) is an alloy of copper & Zinc, Copper & silver, Copper & aluminium.

3)

Forging :

–

Forging is a metal forming process in which the metal or alloy is first heated which the metal or alloy is first heated & then plastically deformed to desired size & shape by the application of com. force using a band hammer or power hammer.



Application of forming : Connecting rods are made by forging only.

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Comp. force upper die

Lower stationary die Fig. open die forging 

Types of forging : 1)

Open die forging

2)

Closed die forging

3)

Upset / M/c forging

Upper die (britlle hard)

Workpiece (ductile)

Fig - closed die forging

Workpiece

Die

Moving die Fig. Upset /m/c forging

Applications : Heads of bolt 4)

Sheet Metal Working :

–

Sheet metal working is the process of manufacturing the components or the parts from sheet metal of thick ranging from 0.1 mm to about 6-8 mm.

–

The tools used for sheet metal working are called die & punch. Punch

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a)

Punching - is the operation of producing circular hole in a sheet metal by using punch & die.

Required component

b)

Piercing - is the operation of producing a hole of any desired shape in a sheet metal by using a punch & a die.

c)

Blanking - is the operation of cutting out a piece of reqd. shape from metal sheet using a punch & a die. Required components

d)

Perforating - is the operation of producing a no.of evenly spaced holes in a metal sheet using a punch & die.

e)

Lancing - is the operation of cutting a part of metal sheet through some portion of it’s length & then bending the cut portion.

f)

Notching - is the operation of removal of small part of metal sheet of the desired shape from edge of the metal sheet.

5)

Sheet Metal Forming :

–

It is the process in which the flat plate of metal sheet is converted into a desired shape without wasting the material. a)

Deep drawing : Punch

-

Deep drawing is the process of forming a flat metal sheet into 3-D hollow shape by the means of a punch that causes the metal to flow into die cavity.

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Die

Die

Application : Cans, Cups b)

Bending punch :

sheet metal

Die c)

Coning : Punch sheet metal

Final component

d)

Write drawing & rolling :

ft (Tensile force) Wire Circular rod

e)

Rolling : Rollers + H2

H1

H2 < H1 +

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6)

Fabrication :

–

Is the process of bldy M/c structure (bridges, boilers) by the use of 1)

Metal cutting

2)

Metal forming

3)

Machining

4)

Metal joining

5)

Final assembly

6)

Inspection

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Machine Tools ============================================================================================== –

Maching or metal cutting process is the process of removing material in the form of chips by the means of cutting tools. So as to give desired size & shape to the components.

–

The commonly used machining or metal cutting process are turning, drilling, milling & shoping.

–

Surface finishing process is the process of imarting good surface finish & high dimensions accuracy to the already machined workpiece with negligible removal of the material.



Types of Machine Tools : Metal cutting M/c tool

Surface finishing M/c tool

1)

Lathe M/c

1)

Grinding M/c

2)

Drilling M/c

2)

Honing M/c

3)

Milling M/c

3)

Lapping M/c

4)

Shaping M/c

4)

Polishing M/c

1)

Lathe Machine :

–

It is the M/c basically used for removing the underable material in the form of chips from undesirable material in the form of chips from the cylindrical surface.

–

In lathe M/c the workpiece to be machined is held firmly & rotated about it’s axis because of this reason the lathe M/c is also known as turning M/c.



Types of Surfaces Machined : a)

Cylindricl Surface : Cutting tool moves parallel to the axis of the workpiece (turning)

b) 

Flat Surface : Cutting tool moves 1er to the axis of the workpiece (facing)

Basic Element of Lathe M/c : 1)

Bed :

–

Bed is the base of the lathe made from cast iron.

–

The top of the bed has two guide ways to provide the support & the sliding sur faces for carriage & tailstock.

2)

Headstock :

–

Functions :

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1)

To support the spindle. spindle is a hollow rotating shaft used for holding the workpiece with the help of work holding device such as chuck.

2)

To house the main drive. The function of the main drive is to drive the spindle & to change the spindle speed. The main drive is powered by an electric motors.

3)

Tailstock :

–

Tailstock can be moved along the guidewas on the lathe bed.

–

Tailstock is used to hold the dead centre which can support the long workpieces.

–

Tailstock is used hold the tools like drill.

4)

Carriage :

–

The carriage is located b/w the head stock & tail stock.

–

It slides along the guide ways on the lathe bed. Function of carriage - 1) 2)



To hold the cutting tool To give longitudinal & cross feed to the cutting tool.

Part of Carriage : 1)

Apron : Apron is the mechanism of the carriage used for manual & mechanised movements along the longitudinal axis of lathe.

2)

Cross slide : Gives cross - feed (Motion  er to the longitudinal axis of lathe)

3)

Compound Rest : It can be turned at any angle in the horizontal plane to facilitate toper turning.

4)

Tool post : It’s function is to hold the cutting tool.

5)

Lead screw : It is used for giving the machanised motion for cutting thereads on the workpiece.

6)

Feed drive : Feed drive is used to transmit the power & motion from main drive to the lead screw.

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Types of operations performed on lathe M/c : a)

Turning : Is the operation of removing the material from cylindrical surface of workpiece to reduce it’s diameter.

b)

Taper turning :

c)

Facing is the operation of removing the material from end surface or the face of workpiece used for reducing the length of the workpiece.

d)

Chamfering : Is the process of bevelling the sharp ends of the workpiece.

–

If is provided to avoid the injuries to the persons handling the finished products.

e)

Grooving :

cutting tool

–

It is the process of providing a narrow groove on the cylindrical surface of the workpiece.

f)

Parting : Is the process of cutting the work into two parts.

g)

Drilling :

h)

Boring : Is the process of enlarging the already existing hole in the workpiece.

Enlarged hole

i)

Thread cutting :

2)

Drilling Machine :

–

Drilling is the process of making cylindrical holes in the workpieces with the help of a tool called drill (Multi pt. cutting tool)

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Basic element of drilling M/c :

A]

Base : Is the lowermost part of the drilling m/c which supports the entire structure.

B]

Column : Is the vertical part fixed on the base. It supports all other elements of drilling M/c.

C]

Work Table : Is has two types of motions. 1)

Up & down motion along the column.

2)

Swing about the axis of column.

Swing

D]

Drilling head : Is mounted on the top of the column. It consist of drive mechanism used for driving spindle. If consist of electric motor & gear box.

E]

Spindle : Is provided with a rotary motion. It supports the drill & imparts rotary motion to it.



Types of operation performed on drilling M/c. 1)

Drilling

2)

Boring

3)

Reaming : Is the process of smoothly finishing & accurately sirling the drilled hole.

After Reaming

4)

Spot facing :

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5)

Counter Sinking : Is the process of cham ferring the entrance of the drilled hole.

6)

Tapping :

Is the process of making internal threads in the drilled hole. 7)

Trepanning : Is the process of making a large hole by removing the metal along the cir cumference of hole.

3)

d Milling Machine :

–

Milling m/c are used to produce the components having flat as well as curved shapes having flat as well as curved shapes.

–

The complex shapes which can not be produced on other m/c tools can be pro duced by milling M/c.

–

Milling is the process of removing the material from workpiece by feding a workpiece past rotating multi. pt cutting tool called as milling cutter.

Milling cutter Workpiece 

Basic Elements of Milling M/c : 1)

Base : Base is the lowermost part of milling m/c which support whole m/c.

2)

Column : Column is the vertical part fixed on the base. It support all other elements of M/c.

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3)

Knee : Is supported on the elevating screw & slides up & down along the vertical guideways on column face.

4)

Saddle : Saddle is mounted on knee. It supports the table & provides cross-feed to the table.

5)

Table : The table is mounted on the saddle. The table travels longitudinally in the guide ways provided on saddle.

6)

Arbour : Is an accurately machined shaft which is used for holding & driving the milling cutter. It is driven by the spindle & spindle is driven by electric motor.

4)

Grinding Machine :

–

Grinding is the process of imparting good surface finish & high dimensional accuracy to the components with negligible removal the material by the use of rotating abrasived tool colled grinding weheel.

–

Grinding wheels are made of fine grains of abrasive materials. held together by a bonding material.

Ceramics

–

Each grain of abrasive material acts like a single pt cutting tool. Power Saw :

–

Power saw is a M/c used for cutting a work pieces to the desired length.



Need of NC & CNC Machine tools : The aim of any manufacturing industery is – 1)

To manufacture the components of desired quality.

2)

To manufacture the components at high rate of production.

To manufacture the comp. at min coast. In order to achieve this the intervention should be either eliminated or minimised. This can be made possible only with the use of automatic M/c tools i.e NC & CNC m/c tools.

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A]

NC (Numerical Control) Machine tools :

–

Numerical control can be defined as the programable automation in which the process is controlled by numbers, letters & symols.

–

The NC program consist of set of instructions for rcontrolling the motion of drives as well as motion of cutting tools.



Basic elements of Nc M/c tool : 1)

Part drawing & part program :

–

Using the part drawing the part program is written in coded form using no letters & symbols.

2)

Program Tape : The part program is entered on program tape.

–

It may be a paper tape, magnetic tape or magnetic disc.

–

In case of paper tape the part program is entered in the form of punched holes.

3)

Machine control unit :

–

M/c control unit consist of tape reader & controller.

–

The program tape is read by the tape reader. The controller take I/p from tape reader & actuates the drives & tools of the machine tool.

4)

M/c tool : Is operated by the controller of MCU

B]

CNC Machine Tool : (Computerised Numerical Control)

–

CNC m/c tool is the programable m/c tool which consist of 1)

Micro computer or mini computor used as M/c.

2)

Various function are controlled by part programe entered through the computer I/p devices like keyboard & CD.



Basic Elements :

1)

Part drawing & part programme : Using the part drawing the part programe is written.

2)

I/p - o/p devices : The part programe is entered into the computer using I\p devices like keyboard, mouse, CD etc.

3)

Computer Based MCU :

–

Consist of CPU & controller.

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–

Part programme is read by CPU of computer.

–

The controller takes I/p from CPU & actuates the drives & tools of the M/c tool.

4)

M/c tool : M/c tool is operated by controller of computer based MCU.

5)

Feed back unit : Takes feed back from M/c tool & gives it to the computer based M/c control unit.

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UNIT : - 1 THERMODYNAMICS ============================================================================================= 1.

Which of the following variables controls the physical properties of a perfect gas (a) pressure

2.

(b) Celsius

(c) Fahrenheit

(d) Kelvin

(b) gram

(c) tonne

(d) newton

(b) minute

(c) hour

(d) day

(b) centimeter

(c) kilometer

(d) millimeter.

(c) joule/s

(d) joule/m

The unit of energy in S.I. units is (a) watt

8.

(d) all of the above

The unit of length in S.I. units is (a) meter

7.

(c) GayLussac law

The unit of time in S.I. units is (a) second

6.

(b) Charles’law

The unit of mass in S.I. units is (a) kilogram

5.

(d) all of the above

The unit of temperature in S.I. units is (a) Centigrade

4.

(c) volume

Which of the following law is applicable for the behavior of a perfect gas (a) Boyle’s law

3.

(b) temperature

(b) joule

According to GayLussac law for a perfect gas, the absolute pressure of given mass varies directly as (a) temperature (b) remains constant,if volume and temperature are kept constant (c) absolute temperature, if volume is kept constant (d) volume, if temperature is kept constant

9.

General /Ideal gas equation is (a) PV = nRT

10.

(b) PV = mRT

(c) PV = C

(d) PV=KiRT

According to Dalton’s law, the total pres sure of the mixture of gases is equal to (a) greater of the partial pressures of all (b) average of the partial pressures of all (c) sum of the partial pressures of all (d) sum of the partial pressures of all divided by average molecular weight

11.

The unit of pressure in S.I. units is (a) kg/cm2

12.

(b) mm of water column

(c) pascal

(d) bars

A closed system is one in which (a) mass does not cross boundaries of the system, though energy may do so (b) mass crosses the boundary but not the energy

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(c) neither mass nor energy crosses the boundaries of the system (d) both energy and mass cross the boundaries of the system 13.

14.

15.

Temperature of a gas is produced due to (a) its heating value

(b) kinetic energy of molecules

(c) repulsion of molecules

(d) attraction of molecules

According to kinetic theory of gases, the absolute zero temperature is attained when (a) volume of the gas is zero

(b) pressure of the gas is zero

(c) kinetic energy of the molecules is zero

(d) specific heat of gas is zero

Kinetic theory of gases assumes that the collisions between the molecules are (a) perfectly elastic

16.

17.

(b) perfectly inelastic (c) partly elastic

(d) partly inelastic

Superheated vapour behaves (a) exactly as gas

(b) as steam

(c) as ordinary vapour

(d) approximately as a gaS

Absolute zero pressure will occur (a) at sea level (b) at the center of the earth (c) when molecular momentum of the system becomes zero (d) under vacuum conditions

18.

The unit of power in S.I. units is (a) newton

19.

20.

(b) pascal

(c) watt

(d) joule.

The condition of perfect vacuum, i.e., absolute zero pressure can be attained at (a) a temperature of 273.15°C

(b) a temperature of 0°C

(c) a temperature of 273 °K

(d) a negative pressure and 0°C temperature

Intensive property of a system is one whose value (a) depends on the mass of the system, like volume (b) does not depend on the mass of the system, like temperature, pressure, etc. (c) is not dependent on the path followed but on the state (d) is dependent on the path followed and not on the state

21.

Specific heat of air at constant pressure is equal to (a) 0.17

22.

(c) 1.005

(d) 1.0

Specific heat of air at constant volume is equal to (a) 0.718

23.

(b) 0.21

(b) 0.21

(c) 1.005

(d) 1.0

Characteristic gas constant of a gas is equal to (a) C/Cv

(b) Cv/Cp

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(d) Cp + Cv

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24.

Which of the following is mayers equation (a) C/Cv

25.

27.

28.

29.

(d) Cp + Cv=R

(b) 0.24

(c) 0.1

(d) 1.41

Boyle’s law i.e. pV = constant is applicable to gases under (a) all ranges of pressures

(b) only small range of pressures

(c) high range of pressures

(d) steady change of pressures

Solids and liquids have (a) one value of specific heat

(b) two values of specific heat

(c) three values of specific heat

(d) no value of specific heat

The same volume of all gases would represent their (a) densities

(b) specific weights

(c) molecular weights

(d) gas characteristic constants

One watt is equal to (a) 1 Nm/s

30.

(c) Cp Cv =R

The ratio of two specific heats of air is equal to (a) 0.17

26.

(b) Cp-Cv = 0

(b) 1 N/mt

(c) 1 Nm/hr

(d) 1 kNm/hr

An open system is one in which (a) mass does not cross boundaries of the system, though energy may do so (b) neither mass nor energy crosses the boundaries of the system (c) both energy and mass cross the boundaries of the system (d) mass crosses the boundary but not the energy

31.

An isolated system is one in which (a) mass does not cross boundaries of the system, though energy may do so (b) neither mass nor energy crosses the boundaries of the system (c) both energy and mass cross the boundaries of the system (d) mass crosses the boundary but not the energy

32.

33.

Gases have (a) only one value of specific heat

(b) two values of specific heat

(c) three values of specific heat

(d) no value of specific heat

According to Avogadro’s Hypothesis (a) the molecular weights of all the perfect gases occupy the same volume under same conditions of pressure and temperature (b) the sum of partial pressure of mixture of two gases is sum of the two (c) product of the gas constant and the molecular weight of an ideal gas is constant (d) gases have two values of specific heat

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34.

35.

Mixture of ice and water form a (a) closed system

(b) open system

(c) isolated system

(d) heterogeneous system

Which of the following is not the intensive property (a) pressure

36.

(b) temperature

(c) density

(d) heat

The value of the product of molecular weight and the gas characteristic constant for all the gases in S.I. unit is (a) 29.27 kgfm/mol°K (b) 8.314kJ/kmol°K

37.

(c) 848kgfm/mol°K

(d) 427kgfm/mol°K

Universal gas constant is defined as equal to product of the molecular weight of the gas and (a) specific heat at constant pressure (b) specific heat at constant volume (c) ratio of two specific heats (d) gas constant

38.

Extensive property of a system is one whose value (a) depends on the mass of the system like volume (b) does not depend on the mass of the system, like temperature, pressure, etc. (c) is not dependent on the path followed but on the state (d) is dependent on the path followed and not on the state

39.

40.

The statement that molecular weights of all gases occupy the same volume is known as (a) Avogadro’s hypothesis

(b) Dalton’s law

(c) Gas law

(d) Law of thermodynamics

Work done in a free expansion process is (a) + ve

41.

(d) maximum

(b) Joule’s law

(c) Regnault’s law

(d) Boyle’s law

Which law state that specific heat of a gas remains constant at all temperatures and pressures (a) Charles’ Law

43.

(c) zero

Which law states that the internal energy of a gas is a function of temperature (a) Charles’ law

42.

(b) ve

(b) Joule’s Law

(c) Regnault’s Law

(d) Boyle’s Law

If gas is heated against a pressure, keeping the volume constant, then work done will be equal to (a) + v

44.

(b) ve

(c) zero

(d) pressure x volume

Properties of substances like pressure, temperature and density, in thermodynamic coordinates are (a) path functions

(b) point functions

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(c) cyclic functions

(d) real functions

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45.

Which of the following quantities is not the property of the system (a) pressure

46.

47.

49.

50.

52.

(d) heat

(a) pressure and temperature

(b) internal energy, enthalpy and entropy

(c) volume and density

(d) all of the above.

On weight basis, air contains following parts of oxygen (b) 23

(c) 25

(d) 73

Which of the following items is not a path function (a) heat

(b) work

(c) vdp

(d) thermal conductivity.

Work done in an adiabatic process between a given pair of end states depends on (a) the end states only

(b) particular adiabatic process

(c) the value of index n

(d) the value of heattransferred

Heat and work are (a) point functions

51.

(c) specific volume

Which of the following is the property of a system

(a) 21 48.

(b) temperature

(b) system properties (c) path functions

(d) intensive properties

The value of n = 1 in the polytropic process indicates it to be (a) reversible process

(b) isothermal process

(c) adiabatic process

(d) irreversible process

A perfect gas at 27°C is heated at constant pressure till its volume is double. The final temperature is (a) 54°C

53.

(b) 327°C

(c) 108°C

(d) 654°C

If value of n is infinitely large in a polytropic process pV” = C, then the process is known as constant ……. process (a) volume

54.

(b) pressure

(c) temperature

(d) enthalpy

The index of compression n tends to reach ratio of specific heats when (a) flow is uniform and steady

(b) process is isentropic

(c) process is isothermal (d) process is isentropic and specific heat does not change with temperature 55.

56.

Change in enthalpy of a system is the heat supplied at (a) constant pressure

(b) constant temperature

(c) constant volume

(d) constant entropy Ans: a

The term N.T.P. stands for (a) nominal temperature and pressure

(b) natural temperature and pressure

(c) normal temperature and pressure

(d) normal thermodynamic practice

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57.

A heat exchange process in which the product of pressure and volume remains constant is known as

58.

59.

(a) heat exchange process

(b) throttling process

(c) isentropic process

(d) hyperbolic process.

In an isothermal process, the internal energy of gas molecules (a) increases

(b) decreases

(c) remains constant

(d) may increase/decrease

Zeroth law of thermodynamics (a) deals with conversion of mass and energy (b) deals with reversibility and irreversibility of process (c) states that if two systems are both in equilibrium with a third system, they are in thermal equilibrium with each other (d) deals with heat engines

60.

61.

The basis for measuring thermodynamic property of temperature is given by (a) zeroth law of thermodynamics

(b) first law of thermodynamics

(c) second law of thermodynamics

(d) third law of thermodynamics

Work done is zero for the following process (a) constant volume

62.

(c) throttling

(d) all Of the abov

For which of the following substances, the gas laws can be used with minimum error (a) dry steam

63.

(b) free expansion

(b) wet steam

(c) saturated steam

(d) superheated steam

In a nonflow reversible process for which p = (3V+ 15) x 105N/m2,V changes from 1 m3 to 2 m3. The work done will be about (a) 100 xlOO5 joules (b) lxlO5 joules

64.

(d) 10 xlO5 kilo joules

On volume basis, air contains following parts of oxygen (a) 21

65.

(c) 10 xlO5 joules

(b) 23

(c) 25

(d) 77

For which of the following substances, the internal energy and enthalpy are the functions of temperature only (a) any gas

66.

67.

(b) saturated steam

(c) water

(d) perfect gas

In a free expansion process (a) work done is zero

(b) heat transfer is zero

(c) both (a) and (b) above

(d) work done is zero but heat increases

If a gas vapour is allowed to expand through a very minute aperture, then such a process is known as (a) free expansion

(b) hyperbolic expansion

(c) adiabatic expansion

(d) throttling.

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68.

69.

The specific heat of air increases with increase in (a) temperature

(b) pressure

(c) both pressure and temperature

(d) variation of its constituents

If a fluid expands suddenly into vacuum through an orifice of large dimension, then such a process is called

70.

71.

(a) free expansion

(b) hyperbolic expansion

(c) adiabatic expansion

(d) parabolic expansion

Which of the following processes are thermodynamically reversible (a) throttling

(b) free expansion

(c) constant volume and constant pressure

(d) isothermal and adiabatic.

Which of the following processes is irreversible process (a) isothermal

72.

(b) adiabatic

(c) throttling

(d) all of the above

In order that a cycle be reversible, following must be satisfied (a) free expansion or friction resisted expansion/compression process should not be encountered (b) when heat is being absorbed, temperature of hot source and working sub¬stance should be same (c) when heat is being rejected, temperature of cold source and working substance should be same (d) all of the above

73.

For a thermodynamic process to be reversible, the temperature difference between hot body and working substance should be (a) zero

74.

(d) maximum

(d) infinity

Minimum work in compressor is possible when the value of adiabatic index n is equal to (a) 0.75

75.

(b) minimum

(b) 1

(c) 1.27

(d) 1.35

A gas is compressed in a cylinder by a movable piston to a volume onehalf its original volume. During the process 300kJ heat left the gas and internal energy remained same. The work done on gas in Nm will be (a) 300 Nm

76.

(b) 300,000 Nm

(c) 30 Nm

(d) 3000 Nm

Isochoric process is one in which (a) free expansion takes place (b) very little mechanical work is done by the system (c) no mechanical work is done by the system (d) all parameters remain constant

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77.

According to first law of thermodynamics (a) work done by a system is equal to heat transferred by the system (b) total internal energy of a system during a process remains constant (c) internal energy, enthalpy and entropy during a process remain constant (d) total energy of a system remains constant

78.

Energy can neither be created nor destroyed but can be converted from one form to other is inreferred from

79.

(a) zeroth low of thermodynamic

(b) first law of thermodynamics

(c) second law to thermodynamics

(d) basic law of thermodynamics

Change in enthalpy in a closed system is equal to heat transferred if the reversible process takes place at constant (a) pressure

80.

81.

(b) temperature

(c) volume

(d) internal energy

In an isothermal process, the internal energy (a) increases

(b) decreases

(c) remains constant

(d) first increases and then decreases

Change in internal energy in a closed system is equal to heat transferred if the reversible process takes place at constant (a) pressure

82.

(b) temperature

(c) volume

(d) internal energy

(c) thermal capacity

(d) enthalpy.

According to first law of thermodynamics (a) mass and energy are mutually convertible (b) Carnot engine is most efficient (c) heat and work are mutually convertible (d) mass and light are mutually convertible

83.

Total heat of a substance is also known as (a) internal energy

84.

(b) entropy

First law of thermodynamics (a) enables to determine change in internal energy of the system (b) does not help to predict whether the system will or not undergo a change (c) does not enable to determine change in entropy (d) provides relationship between heat, work and internal energy (e) all of the above.

85.

Addition of heat at constant pressure to a gas results in (a) raising its temperature (c) raising its volume

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(b) raising its pressure (d) raising its temperature and doing external work 99

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86.

87.

88.

Carnot cycle has maximum efficiency for (a) reversible engine

(b) irreversible engine

(c) new engine

(d) petrol engine

Measurement of temperature is based on (a) thermodynamic properties

(b) zeroth law of thermodynamics

(c) first law of thermodynamics

(d) second law of thermodynamics

Carnot cycle efficiency depends upon (a) properties of the medium/substance used (b) condition of engine (c) working condition

89.

(d) temperature range of operation

Carnot cycle efficiency is maximum when (a) initial temperature is 0°K (b) final temperature is 0°K (c) difference between initial and final temperature is 0°K (d) final temperature is 0°C

90.

If heat be exchanged in a reversible manner, which of the following property of the working substance will change accordingly (a) temperature

91.

(b) enthalpy

(c) internal energy

(d) entropy

If a system after undergoing a series of processes, returns to the initial state then (a) process is thermodynamically in equilibrium (b) process is executed in closed system cycle (c) its entropy will change due to irreversibility (d) sum of heat and work transfer will be zero

92.

Which of the following represents the perpetual motion of the first kind (a) engine with 100% thermal efficiency

(b) a fully reversible engine

(c) transfer of heat energy from low temperature source to high temperature source (d) a machine that continuously creates its own energy 93.

94.

95.

In a Carnot cycle, heat is transferred at (a) constant pressure

(b) constant volume

(c) constant temperature

(d) constant enthaply

A diathermic wall is one which (a) prevents thermal interaction

(b) permits thermal interaction

(c) encourages thermal interaction

(d) discourages thermal interaction

An adiabatic wall is one which (a) prevents thermal interaction

(b) permits thermal interaction

(c) encourages thermal interaction

(d) discourages thermal interaction

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96.

The heat supplied to the gaS at constant volume is (where m = Mass of gas, cv = Specific heat at constant volume, cp = Specific heat at constant pressure, T2 – T1 = Rise in temperature, and R = Gas constant) a) mR(T2 – T1) b) mcv(T2 – T1) c) mcp(T2 – T1) d) D. mcp(T2 + T1)

97.

Compressed air coming out from a punctured football (a) becomes hotter (b) becomes cooler1 (c) remains at the same temperature (d) may become hotter or cooler depending upon the humidity of the surround¬ing air

98.

During throttling process (a) heat exchange does not take place (b) no work is done by expanding steam (c) there is no change of internal energy of steam (d) all of the above

99.

The energy of molecular motion appears as (a) heat

100.

102.

104.

(d) friction

(b) quantity of heat

(c) thermal capacity

(d) work .

Barometric pressure is equal to (a) 760 mm Hg

(b) zero mm Hg

(c) 735.6 mm Hg

(d) 1 mm Hg (e) 100mm Hg.

One barometric pressure or 1 atmospheric pressure is equal to (a) 1 kgf/cnr2

103.

(c) surface tension

Calorie is a measure of (a) specific heat

101.

(b) potential energy

(b) 1.033 kgf/cm2

(c) 0 kgf/cm2 (d) 1.0197 kgf/cm2

The first law of thermodynamics is the law of (a) conservation of mass

(b) conservation of energy

(c) conservation of momentum

(d) conservation of heat

A perpetual motion machine is (a) a thermodynamic machine (b) a nonthermodynamic machine (c) a hypothetical machine (d) a hypothetical machine whose operation would violate the laws of thermodynamics

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105.

106

Kelvin Planck’s law deals with (a) conservation of heat

(b) conservation of work

(c) conversion of heat into work

(d) conversion fo work into heat

According to Clausis statement of second law of thermodynamics (a) heat can’t be transferred from low temperature source to high temperature source (b) heat can be transferred for low temperature to high temperature source by using refrigeration cycle. (c) heat can be transferred from low temperature to high temperature source if COP of process is more than unity (d) heat can’t be transferred from low temperature to high temperature source without the aid of external energy

107.

Thermal power plant works on (a) Carnot cycle

108.

109.

110.

111.

(b) Joule cycle

(d) Rankine cycle

(d) Otto cycle

The efficiency of a Carnot engine depends on (a) working substance

(b) design of engine

(c) size of engine

(d) temperatures of source and sink.

The efficiency of Carnot cycle is maximum for (a) gas engine

(b) well lubricated engine

(d) steam engine

(e) reversible engine.

(c) petrol engine

Carnot cycle is (a) a reversible cycle

(b) an irreversible cycle

(c) a semireversible cycle

(d) a quasi static cycle

What is the state, at which saturated liquid line with respect to vaporisation and saturated vapour line on p-v diagram of pure substance, meet called ?

112.

a. saturation state

b. critical state

c. vaporisation state

d. superheated vapour state

The temperature at which a pure liquid transforms into vapour at constant pressure is called as

113.

a. vaporisation temperature

b. normal temperature

c. saturation temperature

d. none of the above

What is a pure substance ? a. a homogeneous mixture of two substances of same composition b. a substance with constant chemical composition throughout its mass c. both a. and b. d. none of the above

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114.

A pure substance exists in a. solid phase

115.

c. gaseous phase

d. all of the above

c) Transition Vapor

d) None of these

Mixture of liquid and dry vapor is known as a) Wet vapor

116.

b. liquid phase

b) Dry Vapor

Sum of internal energy and term pv is called a) Specific energy

b) Specific enthalpy c) Specific entropy

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d) Total energy

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UNIT-2 Heat Transfer ================================================================================================= 1.

Unit of thermal conductivity in S.I. units is (a) J/m2 sec

2.

(b) J/m °K sec

(c) W/m °K

(d) (b) and (c) above.

Thermal conductivity of solid metals with rise in temperature normally (a) increases

(b) decreases

(c) remains constant

(d) may increase or decrease depending on temperature 3.

Hermal conductivity of nonmetallic amorphous solids with decrease in temperature (a) increases

(b) decreases

(c) remains constant

(d) may increase or decrease depending on temperature 4.

5.

Heat transfer takes place as per (a) zeroth law of thermodynamics

(b) first law of thermodynamic

(c) second law of the thermodynamics

(d) Kirchoff’s law

When heat is transferred from one particle of hot body to another by actual motion of the heated particles, it is referred to as heat transfer by

6.

(a) conduction

(b) convection

(c) radiation

(d) conduction and convection

When heat is transferred from hot body to cold body, in a straight line, without affecting the intervening medium, it is referred as heat transfer by

7.

(a) conduction

(b) convection

(c) radiation

(d) conduction and convection

Sensible heat is the heat required to (a) change vapour into liquid (b) change liquid into vapour (c) increase the temperature of a liquid of vapour (d) convert water into steam and superheat it

8.

The insulation ability of an insulator with the presence of moisture would (a) increase

(b) decrease

c) remain unaffected

(d) may increase/decrease depending on temperature and thickness of insulation 9.

When heat is Transferred by molecular collision, it is referred to as heat transfer by (a) conduction

10.

(b) convection

(c) radiation

(d) scattering

Heat transfer in liquid and gases takes place by (a) conduction

(b) convection

(c) radiation

(d) conduction and convection

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11.

12.

Which of the following is the case of heat transfer by radiation (a) blast furnace

(b) heating of building

(c) cooling of parts in furnace

(d) heat received by a person from fireplace

Heat is closely related with (a) liquids

13.

14.

(b) energy

(c) temperature

(d) entropy

Pick up the wrong case. Heat flowing from one side to other depends directly on (a) face area

(b) time

(c) thickness

(d) temperature difference

Total heat is the heat required to (a) change vapour into liquid (b) change liquid into vapour (c) increase the temperature of a liquid or vapour (d) convert water into steam and superheat it

15.

16.

Cork is a good insulator because it has (a) free electrons

(b) atoms colliding frequency

(c) low density

(d) porous body

Thermal conductivity of water in general with rise in temperature (a) increases

(b) decreases

(c) remains constant

(d) may increase or decrease depending on temperature 17.

Thermal conductivity of air with rise in temperature (a) increases

(b) decreases

(c) remains constant

(d) may increase or decrease depending on temperature 18.

19.

20.

Heat flows from one body to other when they have (a) different heat contents

(b) different specific heat

(c) different atomic structure

(d) different temperatures

The concept of overall coefficient of heat transfer is used in heat transfer problems of (a) conduction

(b) convection

(c) radiation

(d) conduction and convection

The amount of heat flow through a body by conduction is (a) directly proportional to the surface area of the body (b) directly proportional to the temperature difference on the two faces of the body (c) dependent upon the material of the body (d) inversely proportional to the thickness of the body (e) all of the above.

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21.

Which of the following has least value of conductivity (a) glass

22.

(b) water

(c) plastic

(d) rubber (e) air.

Which of the following is expected to have highest thermal conductivity (a) steam

(b) solid ice

(c) melting ice

(d) water

(e) boiling water. 23.

Thermal conductivity of glasswool varies from sample to sample because of variation in (a) composition

(b) density

(c) porosity

(d) structure

(e) all of the above. 24.

Thermal conductivity of a material may be defined as the (a) quantity of heat flowing in one second through one cm cube of material when opposite faces are maintained at temperature difference of 1°C (b) quantity of heat flowing in one second through a slab of the material of area one cm square, thick ness 1 cm when its faces differ in temperature by 1°C (c) heat conducted in unit time across unit area through unit thickness when a temperature difference of unity is maintained between opposite faces (d) all of the above

25.

Which of the following has maximum value of thermal conductivity (a) aluminium

26.

(b) steel

(c) brass

(d) copper

Heat is transferred by all three modes of transfer, viz, conduction, convection and radiation in (a) electric heater

27.

(b) steam condenser

(c) melting of ice

(d) boiler.

The ratio of heat flow Q1/Q2 from two walls of same thickness having their thermal conductivi ties as K1 = 2K2 will be (a) I

28.

29.

(c) 2

(d) 0.25

Heat transfer by radiation mainly depends upon (a) Its temperature

(b) nature of the body

(c) kind and extent of its surface

(d) all of the above Ans: d

Thermal conductivity of wood depends on (a) moisture

30.

(b) 0.5

(b) density

(c) temperature

(d) all of the above

In convection heat transfer from hot flue gases to water tube, even though flow may be turbulent, a laminar flow region(boundary layer of film) exists close to the tube. The heat transfer through this film takes place by (a) convection

(b) radiation

(c) conduction

(d) both convection and conduction

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31.

Heat conducted through unit area and unit thick per unit time when temperature difference between opposite faces is unity,is called

32.

33.

(a) thermal resistance

(b) thermal coefficient

(c) temperature gradient

(d) thermal conductivity

Emissivity of a white polished body in comparison to a black body is (a) higher

(b) lower

(c) same

(d) depends upon the shape of body

A grey body is one whose absorptivity (a) varies with temperature (b) varies with wavelength of the incident ray (c) is equal to its emissivity (d) does not vary with temperature and. wavelength of the incident ray

34.

Fourier’s law of heat conduction is valid for (a) one dimensional cases only (b) two dimensional cases only (c) three dimensional cases only (d) regular surfaces having nonuniform temperature gradients (e) irregular surfaces.

35.

All radiations in a black body are (a) reflected

36.

(b) refracted

(c) transmitted

(d) absorbed

According to Kirchoff’s law, the ratio of emissive power to absorptivity for all bodies is equal to the emissive power of a

37.

(a) grey body

(b) brilliant white polished body

(c) red hot body

(d) black body

Total emissivity of polished silver compared to black body is (a) same

(b) higher

(c) more or less same

(d) very much lower 38.

(e) very much higher.

According to StefanBoltzmann law, ideal radiators emit radiant energy at a rate proportional to

39.

(a) absolute temperature

(b) square of temperature

(c) fourth power of absolute temperature

(d) fourth power of temperature

The unit of Stefan Boltzmann constant is (a) watt/cm2 °K

(b) watt/cm4 °K

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(c) watt2/cm °K4

107

(d) watt/cm2 °K4

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40.

41.

Stefan Boltzmann law is applicable for heat transfer by (a) conduction

(b) convection

(c) radiation

(d) conduction and radiation combined

The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body. This statement is known as (a) Krichoff’s law

42.

(b) Stefan’s law

(c) Wien’ law

(d) Planck’s law

The total emissive power is defined as the total amount of radiation emitted by a black body per unit (a) Temperature

(b) thickness

(c) area

(d) time

(e) area and time. 43.

The ratio of the energy absorbed by the body to total energy falling on it is called (a) Absorptive power (b) emissive power

44.

(c) absorptivity

(d) emissivity

40% of incident radiant energy on the surface of a thermally transparent body is reflected backIf the transmissivity of the body be 0.15, then the emissivity of surface is (a) 0.45

45.

(c) 0.40

(d) 0.75

The emissive power of a body depends upon its (a) temperature

46.

(b) 0.55

(b) wave length

(c) physical nature

(d) all of the above

Two plates spaced 150 mm apart are maintained at 1000°C and 70°C. The heat transfer will take place mainly by

47.

(a) convection

(b) free convection

(c) radiation

(d) radiation and convection

A perfect black body is one which (a) is black in colour (b) reflects all heat (c) transmits all heat radiations (d) Absorbed heat radiations of all wave lengths falling on it

48.

A grey body is one whose absorptivity (a) Varies with temperature (b) varies with the wave length of incident ray (c) varies with both (d) Does not vary with temperature and wave length of the incident ray

49.

Find the wrong statement: Specific heat of a material. (a) Constant for a material

(b) Heat capacity per unit mass

(c) Extensive property

(d) Has units as J/kg-K.

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50.

Polymers have thermal conductivities in the range of (a) < 1

51.

52.

53.

55.

56.

57.

(c) 10-100

(d) > 100

Thermal conductivity in polymers increases with (a) Increase in crystallinity

(b) Decrease in crystallinity

(c) Either

(d) None

Heat transfer deals with the rate of a) work transfer

b) temperature transfer

c) energy transfer

d) none of the above

Which among the following has lowest thermal conductivity among the others ? a) silver

54.

(b) 1-10

b) watery

c) mercury

d) copper

In gases, the transfer of heat takes place by a) volumetric density

b) transporting energy with free electrons

c) unstable elastic collision

d) random molecular collision

How does the heat transfer take place in metals ? a) volumetric density

b) transporting energy with free electrons

c) unstable elastic collision

d) random molecular collision

Internal energy of a substance is associated with a) microscopic modes of energy

b) macroscopic modes of energy

c) both a. and b.

d) none of the above

According to the Fourier’s law of heat conduction, the rate of heat transfer by conduction depends upon a) area of cross section normal to the heat flow b)temperature gradient c) both a. and b. d)none of the above

58.

What is the temperature gradient in the conduction heat transfer ? a) change in temperature per unit change in time b) change in temperature per unit change in distance in the direction of heat flow c) change in temperature per unit change in cross-sectional area normal to the direction of heat flow d) change in temperature per unit change in cross-sectional area parallel to the direction of heat flow

59.

Why is the negative sign introduced in the equation of Fourier’s law of heat conduction ? q = – kA (dT / dx)

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a) because heat transfer rate is inversely proportional to temperature gradient b) because value of thermal conductivity k is negative c) because heat is transferred from higher temperature to lower temperature d) none of the above 60.

The value of thermal conductivity k depends upon a) the material through which the heat is transferred b) the intensity of heat energy which is being transferred c) the area which is parallel to the heat transfer d) all of the above

61.

62.

The materials which have low thermal conductivity are called as a) thermal conductors

b) thermal resistors

c) thermal insulators

d) none of the above

Which law states, “The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings.”

63.

64.

a) Doppler’s Effect

b) Newton’s law of cooling

c) Kirchhoff’s Law

d) Stefan’s Law

Dielectric materials are (a) Insulating materials

(b) Semiconducting material

(c) Magnetic materials

(d) Ferroelectric materials.

Ceramics are good (a) Insulators

65.

66.

67.

(b) conductors

(c) superconductors

(d) semiconductors

How does the radiation heat transfer occur through perfect vacuum ? a) by light waves

b) by electromagnetic waves

c) both a. and b.

d) none of the above

Gray body can emits radiation a) at higher rate than the black body

b) at lower rate than the black body

c) at equal rate than the black body

d) cannot predict

What does the Kirchoff’s identity state ? a) the emissivity and the absorptivity of the black body are same and always less than 1 b) the emissivity and the absorptivity of the black body are same and always more than 1 c) the emissivity and the absorptivity of the black body are same and always equal to 1 d) none of the above

68.

What is the SI unit for Stefan-Boltzmann constant (Ã) ? a) W / m K4

b) W / m2 K4

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c) W / K4 110

d)W K4 / m2

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Unit-3 Power plant ========================================================================================== 1.

Modern steam plants works on which of the following cycles ? a) Carnot cycle

2.

b) Rankine cycle

c) Otto cycle

d) Bell- Coleman cycle

What would be the most important factor under consideration for the site selection of a thermal plant ?

3.

a. Availability of fuel

b. Availability of water.

c. Distance from the populated area

d. Cost and the type of land

Which of the following fuel material occurred naturally? a) U235

4.

b) Pu239

c) Pu241

d) U-233

The function of a moderator is to a) Absorb the part of the Kinetic energy of the neutrons b) extract the heat c) Reflect back some of the neutrons d) start the reactor

5.

Which of the following is not used as moderator? a) Water

6.

8.

11.

12.

b) Ã1

c) 1

d) < 1

a) extract heat from reactor

b) slow down neutrons

c) control the reaction

d) reflect the neutrons Ans:a

Which of the following has highest moderating ratio ? b ) H2O

c) Carbon

d) Helium

Out of the following which one is not a unconventional source of energy ? (a) Tidal power

10.

d) boron

The function of coolant is to

a) D2O 9.

c) graphite

When the control rods are inserted into the reactor, K (Multiplication factor) becomes a) 0

7.

b) heavy water

(b) Geothermal energy(c) Nuclear energy

(d) Wind power

Pulverized coal is (a) Coal free from ash

(b) Non-smoking coal

(c) Coal which bums for long time

(d) Coal broken into fine particles.

Heating value of coal is approximately (a) 1000-2000 kcal / kg

(b) 2000-4000 kcal / kg

(c) 5000-6500 kcal / kg

(d) 9000-10,500 kcal / kg.

Coal used in power plant is also known as (a) Steam coal

(b) Charcoal

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(c) Coke 111

(d) Soft coal. © VISION ENGINEERING Publications

13.

Which of the following is considered as superior quality of coal ? (a) Bituminous coal

14.

(c) Lignite

(d) Coke.

In a power plant, coal is carried from storage place to boilers generally by means of (a) Bucket

15.

(b) Peat

b) v-belts

(c) Trolleys

(d) Manually.

Live storage of coal in a power plant means (a) Coal ready for combustion (b) Preheated coal (c) Storage of coal sufficient to meet 24 hour demand of the plant (d) Coal in transit.

16.

17.

Pressure of steam in condenser is (a) Atmospheric pressure

(b) More than pressure in boiler

(c) Slightly less than pressure in boiler

(d) much less than pressure in boiler

Equipment used for pulverizing the coal is known as (a) Ball mill

18.

19.

(b) Hopper

(c) Burner

(d) Stoker.

The efficiency of a thermal power plant improves with (a) Increased quantity of coal burnt

(b) Larger quantity of water used

(c) Lower load in the plant

(d) Use of high steam pressures.

Which of the following contributes to the improvement of efficiency of Rankine cycle in a thermal power plant ? (a) Reheating of steam at intermediate stage (b) Regeneration use of steam for heating boiler feed water (c) Use of high pressures (d) all of the above.

20.

In a steam turbine cycle, the lowest pressure occurs in (a) Turbine inlet

21.

22.

(b) boiler

(c) condenser

(d) super heater.

Ash content of coal can be reduced by (a) Slow burning

(b) Washing

(c) Pulverizing

(d) Mixing with high grade coal.

An impulse turbine (a) Always operates submerged (b) makes use of a draft tube (c) is most suited for low head installations (d) operates by initial complete conversion to kinetic energy.

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23.

In a thermal power plant cooling towers are used to (a) Condense low pressure steam (b) Cool condensed steam (c) Cool water used in condenser for condensing steam (d) Cool feed water of boiler.

24.

Which of the following material can be used as a moderator ? (a) Graphite

25.

(c) Beryllium

(d) Any of the above.

In a thermal power plant, heat from the flue gases is recovered in (a) Chimney

26.

(b) Heavy water

(b) De-super heater

(c) Economizer

(d) Condenser.

In a super-heater (a) Pressure rises, temperature drops (b) Pressure rises, temperature remains constant (c) Pressure remains constant and temperature rises (d) Both pressure and temperature remains constant.

27.

Which of the following is not an accessory for a boiler? (a) Feed water pump (b) Condenser

28.

30.

31.

32.

34.

(b) Carbon monoxide (c) Nitrogen

(d) Carbon dioxide.

Geothermal energy is (a) A renewable energy resource

(b) Alternative energy source

(c) Inexhaustible energy source

(d) any of the above.

In hydrothermal source of geothermal energy (a) Hot water or steam is available

(b) Hot gases are available

(c) Molten lava is available

(d) none of the above.

Which power plant is free from environmental pollution problems? (a) Thermal power plant

(b) Nuclear power plant

(c) hydro-power plant

(d) Geothermal energy power plant

Chemical representation for heavy water is (a) h20

33.

(d) Air pre-heater.

Generally the major constituent of exhaust gases from a thermal power plant is (a) Oxygen

29.

(c) Economizer

(b) h2o2

(c) h30

(d) d3o.

A photovoltaic cell converts (a) Heat energy into mechanical energy

(b) Chemical energy into electrical energy

(c) Solar energy into electrical energy

(d) Electrical energy into chemical energy.

As steam expands in turbine (a) Its pressure increases

(b) Its specific volume increases

(c) Its boiling point increases

(d) Its temperature increases.

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35.

36.

Which of the following enters the super heater of a boiler? (a) Cold water

(b) Hot water

(c) Wet steam

(d) Super-heated steam.

Super-heated steam is always (a) At a temperature higher than the saturation temperature corresponding to a steam pressure (b) At a pressure more than the boiler steam pressure (c) Separated from water particles before being supplied to turbine (d) At a pressure less than the maximum cycle pressure.

37.

38.

The equipment installed in power plants to reduce air pollution due to smoke is (a) Induced draft fans

(b) De-super heaters

(c) Electrostatic precipitators

(d) Re-heaters.

A condenser in a thermal power plant condenses steam coming out from (a) boiler

39.

(b) Super-heater

(c) Economizer

(d) Turbine.

In a hydro-electric plant a conduct system for taking water from the intake works to the turbine is known as (a) Dam

40.

41.

42.

(c) Penstock

(d) Surge tank

Advantage of hydro-electric power station is (a) Low operating cost

(b) Free from pollution problems

(c) No fuel transportation problems

(d) all of the above.

Which power plant normally operates at high speeds? (a) Diesel engine plant

(b) Petrol engine plant

(c)Steam turbine plant

(d) hydro-electric power plant

Within the boiler, the temperature of steam is highest in (a) Water drum

43.

(b) Reservoir

(b) Water tubes

(c) Water walls

(d) Super heater.

In hydro power plants (a) Initial cost is high and operating cost is low (b) Initial cost as well as operating costs are high (c) Initial cost is low and operating cost is high (d) Initial cost as well as operating cost is low.

44.

45.

In which of the following power plant the availability of power is least reliable? (a) Solar power plant

(b) wind energy

(c) Tidal power plant

(d) Geothermal power plant.

Photovoltaic solar energy conversion system makes use of (a) Fuel cell

(b) Solar cell

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(c) Solar pond 114

(d) None of the above.

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46.

Solar cells are made of (a) Silicon

47.

48.

(b) Germanium

(c) Silver

(d) Aluminum.

The major disadvantage, with solar cells for power generation is (a) lack of availability

(b) large area requirement

c) variable power

(d) high cost.

The commercial sources of energy are (a) solar, wind and biomass (b) fossil fuels, hydropower and nuclear energy (c) wood, animal wastes and agriculture wastes (d) none of the above

49.

The proper indication of incomplete combustion is (a) high CO content in flue gases at exit (b) high CO2 content in flue gases at exit (c) high temperature of flue gases (d) the smoking exhaust from chimney

50.

In fuel cell, the ______ energy is converted into electrical energy. (a) mechanical

51.

52.

54.

(d) sound

(a) using focusing collector or heliostates

(b) using flat plate collectors

(c) using a solar pond

(d) any of the above system

Economiser is used to heat (b) feed water

(c) flue gases

(d) all above

The modern steam turbines are (a) impulse turbines

(b) reaction turbines

(c) impulsereaction turbines

(d) none of the above

The energy radiated by sun on a bright sunny day is approximately (a) 700 W/m2

55.

(c) heat

Solar thermal power generation can be achieved by

(a) air 53.

(b) chemical

(b) 800 W/m2

(c) 1 kW/m2

(d) 2 kW/m2

Carnot cycle comprises of (a) two isentropic processes and two constant volume processes (b) two isentropic processes and two constant pressure processes (c) two isothermal processes and three constant pressure processes (d) none of the above

56.

Direct Solar energy is used for (a) water heating

(b) distillation

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(c) drying 115

(d) all of the above

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57.

The following is indirect method of solar energy utilization (a) Wind energy

58.

(b) biomass energy

(c) wave energy

(d) all of the above

The amount of energy available in the wind at any instant is proportional to ___ of the wind speed.

59.

(a) square root power of two

(b) square root power of three

(c) square power

(d) cube power

The voltage of solar cells is : a) 0.5 to 1 v

60.

b) 1 to 2 v

c) 2 to 3 v

d) 4 to 5 v

c) 5.0 watts

d) 10 watts

The output of solar cells is of the order of : a) 0.5 watts

b) 1.0 watts

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UNIT I Introduction to Mechanical Engineering : Chapter 1 ================================================================================================= Q. 1

The machine is capable of : a) creating energy b) creating and transforming energy c) transforming and transferring energy d) creating, transforming and transferring energy.

Q.2

The device which receives an energy and converts it into useful work is known as a) machine

Q.3

b) mechanism

c) electric motor

d) both

The machine that converts electrical energy to mechanical energy and finally to hydraulic energy is a) hydraulic turbine

Q.4

c) hydraulic motor

d) machine element

An individual part of a machine which performs a specific task is known as a) system

Q.5

b) pump-set

b) mechanism

c) body

d) machine element

Which of the following is not a function of machine element ? a) Holding the different components of machine b) Supporting the different components of machine c) Modifying the different components of machine d) Transmitting the power

Q.6

Q.7

The following is not a type of machine elements : a) Lifting type elements

b) Holding type elements

c) Supporting type elements

d) Power transmitting elements

The following is not an example of holding type element : a) Gear

Q.8

c) gear

d) gear

b) gear

c) key

d) cotter

b) Shaft

c) Gear

d) Belt

The example of power transmitting element is, a) axle

Q.12

b) shaft

The following is not a power transmitting element : a) Bearing

Q.11

d) Rivet

The example of supporting type element is, a) bearing

Q.10

c) Cotter

The example of holding type elements is, a) bearing

Q.9

b) Key

b) bearing

c) gear

d) all (a),(b) and (c)

The following machine element can not be used for power transmission : a) Belt

b) Axle

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c) Shaft 117

d) All (a),(b) and (c) © VISION ENGINEERING Publications

Q.13

Find the odd machine element from the following : a) Axle

Q.14

c) Shaft

d) Bracket

Find the odd machine element form the following : a) Shaft

Q.15

b) Bearing

b) Axle

c) Chain

d) Belt

In case of machine, a) input energy can be less than output work b) input energy can be more than output work c) both the statements (a) and (b) are correct d) both the statements (a) and (b) are incorrect.

Q.16

A shaft is a a) stationary member used to transmit power and motion b) rotating member used to transmit power c) horizontal member used to support gears and pulleys d) horizontal member used to support machines.

Q.17

The cross-section of shaft may be a) solid circular

Q.18

b) hollow circular

c) square

d) both (a) and (b)

Which of the following is a secondary shaft which is drivenby the main shaft through belt, chain or gear drive and from this the power is supplied to the different machines ? a) Line shaft

Q.19

b) Counter shaft

c) Machine shaft

d) Crank shaft

Shafts are classified as : a) Transmission shafts, machine shafts and axles b) Transmission shafts and machine shafts c) Counter shafts and crank shafts d) Line shafts and spindles.

Q.20

Shaft can not be made of : a) plain carbon steel b) alloy steel

Q.21

c) spindle

d) a;; (a), (b) and (c)

b) Spindle

c) k shaft

d) All (a), (b) and (c)

which of the following shafts is not directly connected to prime mover ? a) Line shaft

Q.24

b) counter shaft

Which of the following shafts is used for transmitting the power to more than on machine ? a) Counter shaft

Q.23

d) both (b) and (c)

The example o0f machine shaft is, a) line shaft

Q.22

c) cast iron

b) Spindle

c) counter shaft

d) Both (b) and (c)

The following property is undesirable for shaft : a) Ductility

b) Brittleness

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c) Fatigue strength 118

d) Resilience

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Q.28

A non-rotating machine element which is used to support rotating machine elements, like, wheels, pulley, etc. is known as a) shaft

Q.29

b) spindle

c) axle

d) bracket

Which of the following statement is correct ? a) Shaft is a short rotating element while axle is a long rotating element b) Shaft is a rotating element used for mounting pulley while axle is rotating element used for mounting wheels. c) Shaft is a rotating element while axle is a non-rotating element d) Shaft is a non-rotating element ahile axle is a rotating element.

Q.30

Following is a rotating element used for transmitting power from one element to another : a) axle

Q.31

b) crankshaft

c) Transmission shaft d) Both (b)and (c)

b) bending moment

c) axial force

d) all (a),(b)and (c)

b) bending moment

c) axial force

d) (b) and /or (c)

Axle is subjected to a) torque

Q.34

d) Both (a) and (b)

The transmission shafts are definitely subjected to a) torque

Q.33

c) Rod

The following is not an example of machine shaft. a) Spindle

Q.32

b) Shaft

The function of key is, a) to prevent the relative motion between the shaft and the hub of rotating element b) to fix bearing on shaft c) to mount wheel on axle d) both (a) and (b)

Q.35

Q.36

Key is used on shaft to secure a) rolling contact bearing

b) sliding contact bearing

c) gear

d) all (a),(b) and (c)

Key is generally made of a) steel

Q.37

b) cast iron

c) Aluminium

d) (b) or (c)

Which of the following statement is correct? a) Shaft is made of weaker material b) Key is made of weaker material c) Both shaft and key are made of weaker material d) Both shaft and key are made of stronger material.

Q.38

The most widely used type of sunk key is a) saddle key

b) round key

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c) rectangular key 119

d) tangent key

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Q.39

Rectangular key is a type of a) square key

Q.40

c) saddle key

d) non of the above

c) woodruff key

d) none of the above

Square key is a type of a) saddle key

Q.41

b) woodruff key

b) sunk key

If the key is half in key-way of the shaft and half in the key-way if the hub if the rotating element, then it must be a a) saddle key

Q.42

d 4

c) Tangent key

d) taper key

b) w 

d d and h  4 6

c) w 

d d and h  6 4

d) w 

d 2 and h  d 4 3

b) rectangular key

c) tangent key d) saddle key

Which of the following is a parallel key ? a) feather key

Q.48

b) splines

The key that weakens the shaft is a) woodruff key

Q.47

d) none of the above

In rectangular key, a) w  h 

Q.46

c) sunk key

Which of the following keys is suitable for taper shafts? a) woodruff key

Q.43

b) splines

b) Gib-headed key

c) rectangular key

d) woodruff key

The splines are a) integral with hub b) integral with shaft c) integral with both hub and shaft d) neigher integral with hub nor integral with shaft

Q.49

Q.50

The key that permits relative axial motion between shaft and hub is called are: a) rectangular key

b) woodruff key

c) gib head key

d) splines

The __ are taperless a) splines

Q.51

Q.54

b) gib-headed keys

c) splines

d) feather keys

The following type of key is used in automobile gear boxes : a) splines

Q.53

c) tangent keys d) all (a), (b) and (c)

The multiple key is also known as a) woodruff keys

Q.52

b) gib-headed keys

b) Tangent key

c) Kennedy key

d) Both (a) and (c)

Coupling is used for a) connecting two axles

b) connecting two transmission shaft

c) connecting axle with the shaft

d) both (b)and (c)

coupling is used to connect two a) axles

b) shafts

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c) rods 120

d) all (a), (b)and (c) © VISION ENGINEERING Publications

Q.55

Two transmission shafts are connected by a) key

Q.56

Q.57

b) coupling

c) clutch

d) (a) or (b)

The flange coupling transmits a) torque

b) torque3 and axial force

c) torque, axial force and bending moment

d) axial force

Coupling is used for transmitting a) torque from one axle to another

b) force form one shaft to another

c) bending moment from one shaft to another d) none of the above Q.58

Which of the following is not a rigid coupling ? a) Oldham coupling

Q.59

b) Muff coupling

c) clamp coupling

d) Flange coupling

Which of the following statements is incorrect ? a) Rigid couplings are used to connect two shafts which are perfectly aligned b) Rigid couplings are capable of tolerating misalignment between two shafts. c) Rigid couplings are used for transmitting the torque d) all of the above

Q.60

Couplings are used to connect two shafts which are a) perfectly aligned. b) having small amount of lateral misalignment c) having small amount of angular misalignment d) all of the above

Q.61

The following type of coupling is used for connecting two shafts having small amount of misalignment :

Q.62

a) rigid flange coupling

b) muff coupling

c) split-muff coupling

d) none of the above

The following type of coupling is suitable for connecting two shafts which are perfectly aligned as well as connecting two shafts having small amount of misalignment:

Q.63

a) Bushed-pin type coupling

b) rigid flange coupling

c) split-muff coupling

d) None of the above

The ____ couplings are used to connect two shafts which are perfectly aligned. a) universal

Q.64

c) Oldham

d) all (a), (b) and (c)

The ____ is not capable of absorbing shocks and vibrations. a) flange coupling

Q.65

b) rigid

b) muff coupling

c) split-muff coupling d) all (a),(b)and (c)

____ is not a type of coupling a) Muff coupling

b) compression coupling

c) shaft coupling

d) clam coupling

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Q..66 The ____ is a type of rigid coupling.

Q.67

Q.68

Q.69

a) flange coupling

b) universal coupling

c) Oldham's coupling

d) none of the above

The ___ is capable of absorbing shocks and vibrations. a) flange coupling

b) muff coupling

c) bushed-pin type coupling

d) none of the above

_____ is a type of flexible coupling. a) Bushed-pin type coupling

b) Oldham's coupling

c) Universal coupling

d) All (a),(b) and (c)

The ____ couplings are used to connect two shafts having small amount of lateral or angular misalignment. a) flexible

Q.70

Q.71

b) take axial force

c) take bending moment

d) both (a)and (c)

The number of bolts used in flange coupling can be :

Q.76

c) 7

d) 2

b) 4

c) 6

d) all (a), (b) and (c)

In flange coupling, the two flanges are connected together by b) nuts and bolts

c) key d) all

(a), (b)and (c)

The number of keys used in flange coupling are: a) 1

Q.75

b) 5

the number of bolts used in flange coupling are :

a) screws Q.74

d) none of the above

a) tolerate small lateral misalignment

a) 3 Q.73

c) muff

The flexible flange coupling can

a) 3 Q.72

b) flange

b) 2

c) 3

d) 4

In rigid flange coupling, the torque is transmitted from the driving shaft to the driven shaft a) directly

b) through flanges

c) through key-flanges-bolts-key

d) keys

The appropriate application of rigid flange coupling is : a) Connecting diesel engine to generator. b) Connecting electric motor to centrifugal pump c) Connecting gear box to differential of automobile d) Connecting diesel engine to stone crusher.

Q.77

An electric motor is to be used to drive a centrifugal pump. The connection between two is provided by a) clutch

b) axle

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c) coupling 122

d) rod

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Q.78

In rigid flange coupling, one flange has projected portion and other has a corresponding recess for a) bringing two shafts is line and maintaining alignment b) transmitting torque from one flange to other flange. c) connecting two shafts d) reducing the friction between the two flanges

Q. 79 In flange coupling, the flanges are mounted on the shafts with the help of a) keys Q.80

c) screws

d) (a) or (b)

In rigid flange coupling, the two flanges are connected by a) key

Q.81

b)bolts

b) bolts

c) shaft

d) wire

The following is the path of torque transmission in flange coupling : a) Driving shaft-driving flange-bolts-driven flange-driven shaft b) Driving shaft-key-driving flange-bolts-driven flange-key-driven shaft c) Driving shaft-driven shaft d) diving shaft-driving flange-driven flange-driven shaft.

Q.82

In rigid flange coupling, the following component can be made of costly. The be a) Shafts

Q.83

Q.84

Q.85

b) Flanges

c) Bolts

d) Key

The ___ coupling is more expensive. a) flange

b) muff

c) sleeve

d) flexible flange coupling

The coupling has high torque transmitting capacity and it is costly. Then it be a) Flexible flange coupling

b) Sleeve coupling

c) Flange coupling

d) Muff coupling

The function of bearing is a) to locate two machine parts relative to each other. b) to permit the relative motion between two parts c) to support load

Q.86

d) all of the above.

A mechanical element, which locates two machine parts relative to each other parmits the relative motion between them while carrying the load is known a) bracket

Q.87

c) bearing

d) machine

c) rusting

d) all (a), (b) and (c)

c) vegetable oil

d) all (a), (b)and (c)

In bearings, due to relative motion, there is a a) friction and wear

Q.88

b) frame

b) corrosion

The commonly used lubricants in bearings is a) grease

b) mineral oil

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Q.89

Q.90

The function of lubricant is a) to reduce the friction and wear

b) to dissipate the heat

c) both (a)and (b)

d) to increase the strength of to component.

The bearings are mainly classified as : a) Rolling contact bearings and sliding contact bearings b) Ball bearings and roller bearings c) Friction bearings and antifriction bearings d) Lubricated bearings and non-lubricated bearings.

Q.91

Q.92

Q.93

The anti-friction bearing means a) sliding contact bearing

b) rolling contact bearing

c) bush nearing

d) journal bearing

The following bearing is not an antifriction bearing: a) single-row deep-groove ball bearing

b) Journal bearing

c) cylindrical roller bearing

d) Both (b)and (c)

The rolling contact bearings are also known as a) journal bearings

Q.94

c) journal bearing

d) none of the above

c) journal bearing

d) thrust bearing

the bush bearing is a type of a) ball bearing

Q.95

b) friction bearings b) roller bearing

Rolling contact bearing can take a) radial and axial force b) torque c) bending moment d) radial force, axial force, torque and bending moment

Q.96

The rolling contact bearings are classified as: a) ball bearings and roller bearings b) single-row bearings and double-row bearings c) ball bearings and bush bearings d) cylindrical bearings and thrust bearings

Q.97

In ball bearings, the following part is generally stationary: a) Inner race

Q.98

b) Outer race

c) rolling elements

d) None of the above

In ball bearings, generally a) inner race is rotating and outer race is stationary b) both races are stationary c) inner race is stationary and outer race is rotating d) both races are rotating

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Q.99

In ball bearings, the relative motion is between a) inner race and shaft

b) outer race and frame or casing

c) inner race and outer race

d) none of the above

Q.100 In ball bearings, the relative motion between inner race and outer race is through a) balls or rollers

b) brass bush

c)separator

d) journal

c) inner ring

d) separator

Q.102 The ___ is not a part of ball bearings a) casing

b) outer ring

Q.103 The following element is not used in rolling contact bearings: a) Retainer

b) bush

c) Outer race

d) All of the above

Q.104 In rolling contact bearings, the balls or rollers are inserted between a) moving and moving elements

b) fixed and moving elements

c) fixed and fixed elements

d) none of the above

Q.105 In ball bearings, the rolling elements are made of a) brass

b) cost iron

c) hardened steel

d) copper

Q.106 In ball bearing, the contact between bearings surfaces is a) rolling contact

b) sliding contact

c) linear contact

d) all of the above

c) separator

d) retainer

c) Antifriction

d) none of the above

Q.107 In ball bearing ___ is mounted on the shaft. a) outer race

b) inner race

Q.108 ____ bearings does not required lubrication. a) sliding contact

b) Ball

Q.109 In ball bearings, the balls are separated and evenly spaced around the periphery by a) spacer

b) separator

c) inner race

d) outer race

Q.110 In ball bearings, the function of separator is a) to separate the balls and rollers b) to separate inner rave and outer race c) to separate the rolling elements and space them evenly d) to separate the lubricating oil from the shaft Q.111 The separator is present in a) ball bearings

b) journal bearings

c) guide bearings

d) none of the above

b) outer race

c) balls

d)all (a),(b)and (c)

Q.112 The ball bearing has a) inner race

Q.113 In ball bearings, the outer race is a) supported in casing

b) mounted on shaft

c) supported by bearing

d) supported by key

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Q.114 The most commonly used type of rolling contact bearing is a) single-row deep-groove ball bearing

b) taper roller bearing

c) angular contact bearing

d) bush bearing

Q.116 In rolling contact bearings, the shape of rolling elements is a) spherical

b) cylindrical

c) tapered cylindrical d) all of the above

Q.117 The nature of contact in ball bearing is a) line contact

b) surface contact

c) point contact

d) volume contact

Q.118 The single-row deep-groov3e ball bearings have a) high torque transmitting capacity and high load carrying capacity b) high radial load carrying capacity and moderate axial load carrying capacity c) high axial load carrying capacity and moderate radial load carrying capacity d) high torque transmitting capacity and moderate load carrying capacity Q.119 The nature of contact in roller bearing is a) point contact

b)line contact

c) surface contact

d) area contact

Q.120 For the same shaft diameter, the following bearing has maximum load carrying capacity : a) Ball bearing

b) Single-row bearing

c) Cylindrical roller bearing

d) Deep-groove ball bearing

Q.121 The needle roller bearing is a special type of a) cylindrical roller bearing

b) taper roller bearing

c) spherical roller bearing

d) none of the above

Q. 122 The bearings used in electric motor are a) ball bearings

b) bush bearings

c) journal bearings

d) guide bearings

Q.123 ___ is the mechanical device used to connect or disconnect the driving shaft from driven shaft at the all of the operator a) Coupling

b) Clutch

c) Bearings

d) Brake

Q.124 If the two shafts rotating at different speeds are connected by a device, at the will of the operator, to bring them to the same speed, it is called as a) brake

b) clutch

c) coupling

d) governor

Q.125 ___ can be engaged or disengag3ed at the will of the operator. a) Clutch

b) Coupling

c) Bearing

d) Propeller shaft

Q. 126 Two shafts rotating at different speed are connected by a device, at the will of the operator, to bring them to the some speed is called ___. a) key

b) coupling

c) clutch

d) both (b) and (c)

Q.127 In automobile, ____ is used to disengage the engine from the driving wheels. a) clutch

b) coupling

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c) brake 126

d) propeller shaft © VISION ENGINEERING Publications

Q.128 In a vehicle, ____ is mounted between engine and gear box a) flange coupling

b) clutch

c) propeller shaft

d) universal joint

Q.129 In automobile, clutch is located a) inside gear box

b) between gear box and propeller shaft

c) between engine and gear box

d) between propeller shaft and differential

Q.130 The ____ is capable of transmitting a partial power from input shaft to output shaft. a) flange coupling

b) bush3eed-pin type coupling

c) clutch

d) none of the above

Q.131 In clutch, _____ is a desirable property. a) wear

b) friction

c) hardness

d) surface finish

Q.132 In friction clutch, increase in coefficient of friction a) reduces the efficiency b) reduces the power transmitting capacity c) increases the power transmitting capacity d) both (a) and (b) Q.133 The ___ clutches are used in automobiles. a) plate

b) cone

c) centrifugal

d) jaw

Q.134 _____ are most commonly used types of clutches in automobile. a) Cone clutch and centrifugal clutch b) Single plate clutch and multiple clutch c) Multiplate clutch and centrifugal clutch d) All of the above Q.135 The following mechanical element transmits the power a) Brake

b) Clutch

c) Bearing

d) Both (b) and (c)

c) centrifugal clutch

d) all (a),(b)and (c)

Q.136 ____ is a type of friction clutch. a) Plate clutch

b) cone clutch

Q.137 In single plate clutch, a) the pressure plate is on driving shaft and friction plate is on driven shaft. b) the friction plate is on driving shaft and pressure plate is on driven shaft. c) the friction plate is on driving as well as driven shaft. d) none of the above. Q.138 In a friction clutch, the axial force between driving and driven plates is due to a) friction lining

b) springs

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c) lever

127

d) all.

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Q. 139 In friction clutch, a) driving shaft is splined

b) driven shaft is splined

c) both shafts are splined

d) none of the shaft is splined.

Q. 140 Which of the following statement is incorrect? a) clutch is normally in engaged condition b) friction clutch is positive type c) springs are used in clutch d) sinhle plate clutch is dry type. Q.141 Sprintgs are used in (A) Plate clutches

(b) cone clutches

(c) centrifugal clutches

(d) all (a),(b)and (c)

Q.142 In friction clutches, the friction plate is also known as a) pressure plate

b) clutch plate

c) driving plate

d) all (a),(b)and (c)

Q.143 In friction clutches, the driving plate is also known as a) friction plate

b) pressure plate

c) clutch plate

d) all (a),(b)and (c)

Q.144 In friction clutch, the friction lining is present on a) driving plates

b) driven plates

c) both driving and driven plates

d) either driving or driven plates

Q.145 In friction clutch, asbestos is used as a) insulting material

b) lubricating material

c) protective coating

d) friction material

Q.146 Single plate clutch is normally a) dry type

b) wet type

c) grease lubricated

d) oil lubricated

Q.147 In friction clutch, higher the coefficient of friction, a) lower is the torque transmitting capacity b) lower is the power transmitting capacity c) higher is the torque transmitting capacity d) both (a)and (b) Q.148 In disengaged condition of clutch, a) driving shaft as well as driven shaft are stationary b) driving shaft as well as driven shaft are rotating c) driving shaft is rotating while driven shaft is stationary d) driving shaft is stationary while driven shaft is rotating Q.149 In clutch, during engagement, the axial force between driving and driven plate created by a) clutch pedal

b) clutch cable

c) splined shaft

d) helical compression springs

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Q.150 Single plate clutch is not used in a) buses

b) trucks

c) cars

d) motor cycles

c) single plate

d) all of the above

Q.151 The overall size of ____ clutch is large. a) cone

b) centrifugal

Q.152 If there is a space restriction, the following clutch is not suitable: (a) Cone clutch

(b) Single plate clutch

(c) Centrifugal clutch

(d) All of the above

Q. 153 Which of the following statement is correct ? a) Single plate clutch is wet type while multi-plate clutch is dry type b) Single plate clutch is dry type while multi-plate clutch is wet type c) Single plate clutch as well as multi-plate clutch are wet type d) single plate clutch as well as multi-plate clutch are dry type Q.156 The torque transmitting capacity of dry clutch is a) higher than that of wet clutch

b) lower than that of wet clutch

c) same as that of wet clutch

d) either (b) or (c)

Q. 157 The single plate clutch consists of (a) only one driving plate.

(b) only two driving plates.

c) one or two driving plate.

(d) no driving plate.

Q. 158 The single plate clutch consists of (a) only one driven plate.

(b) only two driven plates.

c) one or two driven plates.

(d) no driven plate.

Q. 159 In single plate clutch, when clutch pedal is pressed, there is a disengagement of (a) friction plate from driven plate.

(b) pressure plate from driving plate.

(c) friction plate from pressure plate,

(d) drivenshaft from splined shaft.

Q. 160 In multi plate clutch, the oil is used for (a) cleaning the friction surface

(b) lubrication.

(c) heat dissipation.

(d) both (b) and (c).

Q.161 In friction clutch, during engagement and disengagement, a) the driven plates moves axially along the shaft. b) the driving plates moves axially along the shaft. c) both the driving and driven plates move axially along the shaft. d) neither the driving nor the driven plate moves axially along the shaft. Q.162 In kinetic energy or potential energy is absorbed and is converted to heatand dissipated to the surrounding air. (a) Bearing

(b) coupling

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(c) brake 129

(d) none of the above

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Q.163 In a process of performing the function, ___ _____

absorbs the energy given up by the

moving system. (a) brake

(b) bearing

(c) coupling

(d) shaft

Q.164 Is a device which applies artificial frictional resistance to a moving machine. (a) Bearing

(b) Clutch

(c) Brake

(d) Both (b) and (c)

(c) potential energy

(d) (b) or (c).

Q.166 The energy absorbed by brake is (a) strain energy.

(b) kinetic energy

Q.166 The energy absorbed by the brake is dissipated in the from of______. (a) heat

(b) kinetic energy

(c) potential energy

(d) all (a), (b) and (c)

Q.167 Brake is used in vehicles. (a) Block

(b) Internal expanding shoe

(c) Disk

(d) (b) and (c)

Q. 168 The following mechanical element is meant for absorbing the kinetic or potential energy of a moving system and converts it into heat which is finallydissipated to the surrounding: (a) Clutch

(b) Brake

(c) Spring

(d) Flywheel

Q. 169 The following mechanical element absorbs the power : (a) Coupling

(b) Flywheel

(c) Brake

(d) None of the above

Q. 170 Brake is not used in vehicles. (a) Band

(b) Disk

(c) Internal expanding shoe

(d) Both (a) and (b)

Q. 171 In disk brake, a) One disk is fixed and other is rotating. b) Both disks are rotating. c) Both disks are stationary so as to stop the vehicle. d) There is only one rotating disk. Q. 172 Disk brake is also known as (a) drum disk brake

(b) caliper disk brake.

(c) internal disk brake

(d) shoe disk brake.

Q.173 Disk brakes are used in motor cycle due to a) high torque transmission capacity

b) high power transmission capacity

c) high mechanical efficiency

d) excellent control

Q.174 Disk brake consists of a) shoes

b) blocks

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c) pads

130

d) none of the above

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Q.175 Racing cars use a) band brake

b) block brake

c) disk brake

d) band and block brake

Q,176 In disk brake, the braking action is due to a) friction between the two rotating disks b) friction between rotating disk and stationary disk c) friction between rotating disk and calipers d) none of the above Q.177 Now a days ____ brake is used in motor cycles. a) bank

b) band and block

c) electric

d) disk

=========================================================================================

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CHAPTER I ==================================================================================================================================

Answer Key =============================================================================== Q.1

(c)

Q.2

(a)

Q.3

(b)

Q.4

(d)

Q.5

(c)

Q.6

(a)

Q.7

(a)

Q.8

(d)

Q.9

(a)

Q.10 (a)

Q.11 (c)

Q.12 (b)

Q.13 (c)

Q.14 (b)

Q.15 (b)

Q.16 (b)

Q.17 (b)

Q.18 (b)

Q.19 (b)

Q.20 (c)

Q.21 (c)

Q.22 (a)

Q.23 (c)

Q.24 (b)

Q.28 (c)

Q.29 (*)

Q.30 (b)

Q.31 (c)

Q.32 (a)

Q.33 (d)

Q.34 (a)

Q.35 (*)

Q.36 (a)

Q.37 (b)

Q.38 (c)

Q.39 (d)

Q.40 (b)

Q.41 (c)

Q.42 (a)

Q.43 (b)

Q.46 (a)

Q.47 (a)

Q.48 (*)

Q.49 (d)

Q.50 (a)

Q.51 (c)

Q.52 (a)

Q.53 (b)

Q.54 (b)

Q.55 (b)

Q.56 (a)

Q.57 (d)

Q.58 (a)

Q.59 (b)

Q.60 (d)

Q.61 (d)

Q.62 (a)

Q.63 (b)

Q64. (d)

Q.65 (c)

Q.66 (a)

Q.67 (c)

Q.68 (d)

Q.69 (a)

Q.70 (a)

Q.71 (a)

Q.72 (d)

Q.73 (b)

Q.74 (b)

Q.75 (c)

Q.76 (b)

Q.77 (c)

Q.78 (a)

Q.79 (a)

Q.80 (b)

Q.81 (b)

Q.82 (b)

Q.83 (d)

Q.84 (a)

Q.85 (c)

Q.86 (c)

Q.87 (a)

Q.88 (b)

Q.89 (c)

Q.90 (a)

Q.91 (b)

Q.92 (b)

Q.93 (c)

Q.94 (c)

Q.95 (a)

Q.96 (a)

Q.97 (b)

Q.98 (a)

Q.99 (c)

Q.100 (a)

Q.101 (a)

Q.102 (a)

Q.103 (b)

Q.104 (b)

Q.105 (c)

Q.106 (a)

Q.107 (b)

Q.108 (d)

Q.109 (b)

Q.110 (c)

Q.111 (a)

Q.112 (d)

Q.113 (a)

Q.114 (a)

Q.115 ()

Q.116 (d)

Q.117 (c)

Q.118 (b)

Q.119 (b)

Q.120 (c)

Q.121 (a)

Q.122 (a)

Q.123 (b)

Q.124 (b)

Q.125 (a)

Q.126 (c)

Q.127 (a)

Q.128 (b)

Q.129 (c)

Q.130 (c)

Q.131 (b)

Q.132 (c)

Q.133 (a)

Q.134 (b)

Q.135 (b)

Q.136 (d)

Q.137 (a)

Q.138 (b)

Q.139 (b)

Q.140 (b)

Q.141 (d)

Q.142 (b)

Q.143 (b)

Q.144 (b)

Q.145 (d)

Q.146 (a)

Q.147 (c)

Q.148 (c)

Q.149 (d)

Q.150 (d)

Q.151 (c)

Q.152 (b)

Q.153 (b)

Q.154 ()

Q.155 ()

Q.156 (a)

Q.157 (c)

Q.158 (a)

Q.159 (c)

Q.160 (c)

Q.161 (a)

Q.162 (c)

Q.163 (a)

Q.164 (c)

Q.165 ()

Q.166 (d)

Q.167 (d)

Q.168 (b)

Q.169 (c)

Q.170 (a)

Q.171 (a)

Q.172 (b)

Q.173 (d)

Q.174 (c)

Q.175 (c)

Q.176 (c)

Q.177 (d)

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Chapter 2 ====================================================================================================================== Q. 1

Q. 2

The prune movers should be ideally designed for (a) high weight to power ratio

(b) high power to weight ratio.

(c) high weight to volume ratio

(d) none of the above.

The example of prime mover is a) electric motor

Q. 3

Q. 5

b) Centrifugal pump

c) Steam turbine

d) I. C. engine

a) machine to prime mover

b) prime mover to prime mover.

c) prime mover to machine

d) all of the above.

Following is not an example of power transmission device : (b) Belt

(c) Chain

(d) Bearing

_____ is an example of power transmission device. a) Gear

Q. 7

d) all of the above.

The power transmission devices are used for transmitting the power from

a) Gears pair Q.6

c) Petrol engine

Find the odd element out from the following list: a) Electric motor

Q. 4

b) diesel engine

(b) Brake

(c) Bearing

(d) All of the above

_____is a mechanism used for transmitting the power and motion from primemover to the machine. a) Drive

Q.8

Q.12

(d) All of the above

(b) Gear drive

(c) Chain drive

(d) All of the above

(b) driven pulley.

(c) belt.

(d) all of the above.

(a) driving pulley to driven pulley

(b) driven pulley to driving pulley.

(c) small pulley to large pulley

(d) large pulley to small pulley.

In ______ drive, power is transmitted because of friction. (b) Gear

(c) Chain

(d) All of the above

(c) Belt

(d) None of the above

In ______ drive, the friction is desirable. . (a) Gear

Q.14

(c) Gear

In belt drive, power is transmitted from

(a) Belt Q.13

(b) Chain

The essential element of belt drive is (a) driving pulley,

Q.11

d) None of the above

_____ is used for transmitting the power between two pulleys. (a) Belt drive

Q.10

(c) Brake

__________ is an example of drive. (a) Belt

Q.9

(b) Bearing

(b) Chain

The drive used for transmitting the power from one shaft to another shaft at considerable distance apart is a) V-belt drive

(b) flat belt drive

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(c) chain drive

(d) gear drive.

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Q.15

In belt drive, higher the co-efficient of friction a) higher is the power and torque transmitting capacity. b) lower is the power and torque transmitting capacity. c) higher is the power transmitting capacity and lower is the torque transmitting capacity. d) lower is the power transmitting capacity and higher is the torque transmitting capacity.

Q.16

If friction is zero, _______ (a) gear

Q.17

drive can not function.

(b) belt

(c) chain

(d) none of the above

In flat belt drive, the surface speed of driving pulley is a) greater than the surface speed of driven pulley b) equal to the surface speed of driven pulley c) less than the surface speed of driven pulley d) can not say

Q.18

Q.19

Q.20

In belt drive, power is transmitted from driving pulley to driven pulley because of a) mass of belt.

(b) surface area of belt.

c) friction between belt and pulley.

(d) all of the above.

In belt drive, driving pulley is also known as (a) head pulley

(b) output pulley

(c) tail pulley

(d) (a) or (b) (a)

In belt drive, driven pulley is also known as a) head pulley

Q.21

(d) (b) or (c).

πdn 60

b) V 

2πdn 60

c) V 

πrn 60

d) V 

60πd n

For flat belt drive, speed ratio is a) i 

Q.24

(c) input pulley

The linear velocity of flat belt is given by expression : (a) V 

Q.22

(b) tail pulley

N (d  t)  n (D  t)

b) i 

N (D  t)  n (d  t)

c) i 

n (D  t)  N (d  t)

d) i 

n (D  2t)  N (d  2t)

In flat belt drive, Speed of driving pulley =3×Speed of driving pulley. Hence a) power on driven pulley = 3 × Power on driving pulley b) power on driven pulley =

1 Power on driving pulley 3

c) power on driven pulley = Power on driving pulley d) power on driven pulley < power on driven pulley Q.25

In a flat belt drive, the torque on driving pulley is 10000 N-mn and speed of pulley is 480 r.p.m. If the reduction ratio is 3, the power transmitted by belt is. a) 1508 kW.

(b) 1.51 kW.

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(c) 502.6 W. 134

(d) 502.6 kW.

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Q.26

In a flat belt drive, the diameter of driving pulley is 190 mm is 10 mm and thickness is 10mm. If speed ratio is 2, the diameter of driven pulley is (a) 90 mm

(b) 85 mm

(c) 380 mm

(d) none of the above

Q. 27 An electric motor running of2880 r.p.m. is used for driving the line shaft flat belt drive. The reduction ratio is 2.6, while belt thickness is 9.51 recommended belt speed is 15 m/s, the diameter of driven pulley should be (a) 90 mm. Q.28

(b) 250 mm.

(c) 100 mm.

(d) 40 mm.

In a flat belt drive, the speed of driving and driven shafts are 1440 r.p.m 360 r.p.m. respectively. The torque on driving shaft is 40000 N-mm thickness of belt is 10 mm, the torque on driven shaft is (a) 160 N-m

Q.29

(b) 10000 N-mm

(c) 10 N-m

(d) none of the above

The flat belt drive is used for the transmission of power from an machine with a reduction ratio of 3. If the diameter and s] pulley are 150 mm and 1000 r.p.m. respectively, the diameter machine pulley are:

Q.30

a) 490 mm and 333.33 r.p.m. respectively

b) 50mm and 333.33 r.p.m. respectively.

c) 450 mm and 3000 r.p.m. respectively

d) 50 mm and 3000 r.p.m. respectively.

The flat belt drive is used for the reduction ration of 2.5 . If the diameter of motor pulley is 250 mm and the speed of motor shaft is1000 r.p.m. a) the diameter of machine pulley is 100 mm and the speed of machine pulley is 2500 r.p.m. b) the diameter of machine pulley is 100 mm and the speed of machine pulley is 400 r.p.m. c) the diameter of machine pulley is 625 mm and the speed of machine pulley is 400 r.p.m. d) the diameter of machine pulley is 625 mm and the speed of machine pulley is 400 r.p.m.

Q.32

The flat belt drive is used for the transmission of power from an electric motor to a machine with a reduction ratio of 2. If the speed of machine pulley is 600 r.p.m. and the torque on machine shaft is 30 N-m, the electric motor power is a) 0.94 kW

b) 1885 kW

c) 3.77kW

d) 1.885 kW

Q. 33 The flat belt drive is used for transmitting the power from an electric motor to a centrifugal pump with a reduction ratio of 3. If the power required to drive the pump is 3 kW, the power rating of an electric motor should be a) 1 kW

(b) 9 kW

(c) 3 kW

(d) 6 kW

Q. 34 In flat belt drive, the arrangement made on the pulley to avoid coming off the belt from the pulley is known as a) crowning

(b) tapering

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(c) gripping

135

(d) tightening.

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Q. 35 In a flat belt drive, if the driving and driven pulleys are rotating at 1500 r.p.m. and 500 r.p.m. respectively , the surface velocity of driving pulley is a) three times the surface velocity of driven pulley. b) 1/3 times the surface velocity of driven pulley. c) same as that of the surface velocity of driven pulley. d) 9 times the surface velocity of driven pulley. Q. 36 Which of the following statement is incorrect ? a) In flat belt drives the slip is more. b) Flat belt drives are larger in size and occupy more space. c) The flat belt can be used to transmit very high power. d) the flat belt can not be used for short centre distance. Q. 37 The cross-section of flat belt is a) square

(b) rectangular

(c) trapezoidal

(d) none of the above.

Q. 38 Width of flat belt is a) equal to its thickness.

b) less than its thickness.

c) substantially higher than its thickness

d) 1.5 to 2.0 times its thickness.

Q. 39 Term crowning is associated with a) chain drive.

(b) flat belt drive

c) V-belt drive

(d) circular belt drive.

Q. 40 Flat belts are used where power to be transmitted is ____ a) high

(b) moderate

(c) veryhigh

d) low

Q. 41 Which of the following drives is least suited for high speed applications ? a) Spur gear drive

(b) V-belt drive

(c) Flat belt drive

(d) Helical gear drive

Q. 42 Which of the following drives has a maximum slip ? (a) V-belt drive

(b) Rope drive

(c) Timing belt drive (d) Flat belt drive

Q. 43 Flat belts are used to transmit a) high power over short centre distance

b) low power over short centre distance.

c) moderate power over long centre distance d) all of the above. Q. 44 The efficiency of flat belt drive is about (a) 97-99 percent

(b) 80-85 percent

(c) 70-75 percent.

(d) 50-60 percent.

(c) Trapezoid

(d) none of the above.

Q. 45 The cross-section of V-belt is (a) Triangle

(b) Inverted triangle

Q. 46 V-belt drives transmit large power compared to the flat belt drives because of: (a) more weight

(b) wedging action

(c) short centre distance

(d) high reduction ratio

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Q. 47 ______ are mounted on grooved pulleys. a) Flat belts

(b) V-belts

(c) Timing belts

(d) All (a), (b) and (c)

Q. 48 The drive most suited for transmitting the power from an electric motor to the reciprocating air compressor is a) flat belt drive

(b) gear drive.

(c) chain drive

(d) V-belt drive.

(c) chain drive

(d) none of the above.

Q. 49 The sheaves are used in a) flat belt drive

(b) V-belt drive

Q. 50 If the centre distance between two shafts is 1 m, the drive mostly suited for the transmission of power is a) flat belt drive Q.51

(b) V-belt drive,

(c) rope drive

(d) gear drive

Which of the following statement is incorrect ? a) V-belt drives can transmit power over long centre distances. b) V-belt drives can transmit large power c) V-belt drives permit high reduction ratio d) Slip is negligible in V-belt drives

Q.52

Four belts are mounted on a pair of pulleys to transmit power. Then it must ___ drive. a) flat belt

Q.53

b) V-belt drive

c) Circular belt drive d) All of the above

b) V-belt

c) timing belt

d) spur gear

In v-belt drive, the pulley groove angle is____. a) 150 to 200

Q.58

d) any of the above

In which of the following drives slip is maximum? a) Flat belt

Q.57

c) V-belt

Which of the following is not suited for long centre distance? a) Flat belt drive

Q.54

b) timing belt

b) 250 to 300

c) 350 to 40

d) 550 to 600

V-belt are classified into five sections A,B,C,D and E, based on ____. a) weight

b) cross-section

c) length

d) power

Q. 59 In V-belt drive, belt is the belt with largest cross-section. (a) F

(b) G

(c) E

(d) D

Q. 60 The following drive is most suited for multiple drive: (a) Flat belt drive

(b) V-belt drive

(c) Timing belt drive (d) Both (b) and (c)

Q. 61 The reduction ratio of V-belt drive is up to (a) 3:1 Q.62

(b) 20 :1

. (c) 15 :1

(d) 7:1

It is used for power transmission over shorter centre distance and it does not require lubrication. It is a

.

(a) flat belt drive

(b) V-belt drive

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(c) chain drive 137

(d) gear drive

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Q.63

Friction is not responsible for transmitting the power in (a) flat belt drive

Q.64

(b) V-belt drive

(c) timing belt drive

Which of the following drives operate without slip ? (a) Timing belt drive (b) Flat belt drive

Q.65

Q.67

Q.68

Q.69

(c) V-belt drive

(d) Both (a) and (c)

In timing belts, power is transmitted due to. (a) friction

Q.66

(d) none of the above.

b) teeth

(c) wedging

(d) centrifugal force

The belt drive which can operate without initial tension is

.

(a) fast and loose pulley drives

(b) V-belt drives

(c) cone pulley drives

(d) timing belt drives

The belt drives are arranged in decreasing order of slip as : (a) Flat belts-V belts-Timing belts

(b) Flat belts-Timing belts-V belts

(c) Timing belts-Flat belts-V belts

(d) V belts-Flat belts-Timing belts

The following two types of belt drives use similar pulleys: a) Flat belt and V-belt

(b) V-belt and Circular belt

(c) V-belt and Timing belt

(d) None of the above

The drive tousedIntransmit a power from an electricmotor pulley rotating m clockwise direction to a machine pulley rotating in a counter clock wipe direction h taunt be a a) flat belt drive

(b) V-belt drive

c) chain drive

(d) taming belt drive

Q. 70 The idler pulley, used in flat belt drive, helps in a) adjusting the belt-tension. b) keeping the axis of the driven shaft at an angle with the axis of the driving shaft. c) changing the direction of rotation of pulley. d) both (a) and (b). Q. 71 The multiple-ply belts are used in ____. a) V- belt drive

(b) flat belt drive

(c) rimingbelt drive

(d) both (a) and (b)

Q. 72 If the driving and driven pulleys are required to rotate in opposite direction, then the type of drive used is _______ . (a) open belt drive

(b) compound belt drive

(c) crossed belt drive

(d) quarter turn belt drive

Q. 73 A flat belt drive used for changing the speed of the driven shaft while the driving shaft runs at constant speed is known as .

Q.76

(a) cone pulley drive

(b) multiple belt drive

(c) compound belt drive

(d) fast and loose pulley drive

In following drive, axes of driving shaft and driven shaft can be at right angles : a) V-belt drive

b) Flat hell drive

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c) Timing heft drive d) None of the above © VISION ENGINEERING Publications

Q. 77 The driven abaft is to be stopped or started whenever desired without stopping the driving shaft the drive used is a) cone pulley drive

(b) com pound belt drive

c) multiple belt drive

(d) fast and loose pulley drive

Q. 78 When the power is to be transmitted from one shaft to the number of parallel shaft the drive used is a) compound belt drive

(b) stepped pulley drive

c) crossed belt drive

(d) none of the above

Q. 79 Thefollowing flat belt drive requires minimum two belts: a) Multiple belt drive

(b) Cone pulley drive

c) Compound belt drive

(d) None of the above

Q. 80 The fallowing flat belt drive is used for transmitting the power from one driving pulley to the number of driven pulleys :

Q.81

Q.82

a) Cone pulley drive

(b) Open belt drive with idler pulley

c) Crossed haft drive

(d) None of the above

_____ is used when the axes of the two shafts are perpendicular. (a) Cone pulley drive

(b) Compound belt drive

(c) Quarter turn belt drive

(d) Multiple belt drive

______ is used when driven shaft is to be stopped without stopping the drive shaft. (a) Past and loose pulley drive

(b) Stepped pulley drive

(c) Compound belt drive

(d) None of the above

Q. 83 There is excessive wear and tear in _____.

Q.84

Q.85

Q 86

(a) open belt drive

(b) compound belt drive

(c) cone pulley drive

(d) crossed belt drive

Idler pulley is used in ________. (a) crossed belt drive

(b) quarter turn belt drive

(c) come pulley drive

(d) none of the above

In a belt drive normally _______. a) upper side is tight side

(b) lower side is tight side

(c) both sides are tight sides

(d) both sides are slack sides

In open belt drive use of idler pulley will help in______. a) achieving high speed ratio b) increasing belt tension c) increasing frictional grip between belt and pulley d) all of the above

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Q.87

Q.88

The following prop0erty is undesirable for belt material : a) High strength

b) Low coefficient of friction

c) Durability

d) Flexibility

Flat belts are made of _____. a) leather

b) polyamide

c) polyester

d) all of the above

Q. 89 Which of the following drives needs lubricant ? a) Flat belt drive Q.90

Q.97

(b) V-belt

(c) rope

d) chain

b) chain drive

c) V-belt drive

d) both (a)and (b)

b) pulleys

c) sheaves

d) sprockets

b) V-belt

c) flat belt drive

d) gear drive

_____ is a positive drive used for transmitting power over the long centre distance. a) Flat belt drive

Q.96

(d) both (a) and (b)

It is positive drive which has two sprockets. Then, it is a ___. a) chain drive

Q.95

(c) belt drive

The driving and driven wheels of chain drive are called as _____. a) rollers

Q.94

(b) rope drive

The polygon effect is related to _____. a) spur gear drive

Q.93

(d) Both (b) and (c)

The sprockets are used in____ drive. a) flat belt

Q.92

(c) Chain drive

The drive does not need the initial tension. Then it must be a ____. a) chain drive

Q.91

(b) V-belt drive

b) V-belt drive

c) Timing belt drive

d) None of the above

The chains are classified as : a) Roller chains and Ball chains

b) Roller chains and Involute chains

c) Roller chains and Inverted tooth chains

d) silent chains and Inverted booth chains

The chains are made of ______. a) steel

b) polyamide

c) leather

Q. 98 The chains are made of number of rigid links connected by _____ a) pin joints

(b) bolted joints

c) welded joints

Q. 99 The type of chain used in motor cycle is _______ a) sprocket chain

(b) roller chain

d) none of the above . (d) none of the above

.

(c) silent chain

(d) all of the above

Q.100 The silent chain is also known as (a) inverted tooth chain.

(b) involute tooth chain.

(c) roller chain.

(d) sprocket chain.

Q.101 Which of the following drives is used for high speed applications ? a) Roller chain

(b) Inverted tooth chain

(c) Flat belt drive

(d) V-belt drive

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Q.102 Inverted tooth chain is also known as _________ a) silent chain

(b) roller chain

.

(c) sprocket chain

(d) conveyor chain

Q.103 ______ drive can be used for long as well as short centre distances. a) Flat belt

(b) V-belt

(c) Chain

(d) All of the above

Q. 104 The drive operate with no slip, can transmit power over long centre distance andrequires lubrication. Then it must be a) chain drive

.

(b) spur gear drive

(c) flat belt drive

(d) all of the above

Q. 105 Positive drive used for the transmission of power over longer centre distance is known as ____. a) flat belt drive

(b) V-belt drive

(c) rope drive

(d) chain drive

(c) Rope

(d) None of the above

Q. 106 ______ drive does not require initial tension. a) Flat belt

(b) V-belt

Q. 107 In gear drive, smaller wheel is called as _______ a) gear

(b) sprocket

.

(c) pinion

(d) worm

Q. 108 In gear drive, larger wheel is called as ______. a) gear

(b) sprocket

Q. 109 The gear tooth profile is ______ a) parabolic

(c) pinion

(d) worm

(c) cycloidal

(d) (b) or (c)

.

(b) involute

Q. 111 In spur gear pair, pitch line velocity of pinion is _____. a) equal to pitch line velocity of gear

b) greater than pitch line velocity of gear

c) less than pitch line velocity of gear

d) (a) or (b)

Q.112 In spur gear pair : np d p zp a) n  d  z g g g

np dg zp b) n  d  z g p g

np dg zg c) n  d  z g p p

d) none of the above

Q. 113 In spur gear pair, the gear ratio is given by ____. np a) n g

dg b) d p

zg c) z p

d) all (a),(b)and (c)

Q. 114 For a spur gear pair, the speed ratio is given by, z g ng (a) i  z  n p p

zg np b) i  z  n p g

zp np c) i  z  n g g

zp ng d) i  z  n g p

dg c) d p

zp d) z g

Q.115 In spur gear pair, the gear ratio is given by, ng a) n p

dp b) d g

Q.116 In gear pair, if Tg is torque on gear and Tp is torque on pinion _____. a) Tg > Tp

c) Tg  Tp

b) Tg < Tp

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141

d) Tg + Tp = constant

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Q.117 The efficiency of spur gear pair is ____. a) 65% to 75%

b) 75% to 85%

c) 85% to 95%

d) above 95%

Q.118 In a spur gear pair, when torque is reduced form input shaft to output shaft. a) The lower is also reduced

b) The power is increased.

c) The power remains unchanged

d) The power depends on the speed

Q.119 In a helical gear pair, the power on pinion shaft is 40 kW. If the reduction 4, the power on gear shaft is _______. a) 10 kW

b) 160 kW

c) 40 kW

d) 44kW

Q.120 The function of gear pair is To increase the torque and reduce the speed from the input shaft output shaft. To increase the speed and reduce the torque from the input shaft output shaft To change the direction of rotation from one shaft to another shaft. All of the above Q.121 The gears used for transmitting the power between two parallel shafts are _____. a) helical gears

b) bevel gears

c) spur gears

d) both (a)and (b)

Q.126 The spur gear pair can be used for reduction ration up to a) 15:1

b) 6:1

c) 40:1

d) 2:1

Q .127 It spur gear, the teeth are cut a) parallel to the aids of the gear

(b) parallel to the plane of rotation

c) inclined to the axis of the gear

(d) none of the above.

Q.128 The spur gears _______

.

a) are easy to manufacture b) do not create axial thrust on shaft c) are not suitable for high speed applications d) all of the above Q.129 The gear pair does not create axial thrust on shafts; has sudden line contact between meshing teeth. Then it must be, a) spur gear pair

(b) herringbone.

(c) helical gear pair

(d) (a) or (b).

Q.130 In a spur gear pair, the rotary speed of pinion is three times the rotary speed of gear. If the pitch line velocity of pinion is 15 m/s, the pitch line velocity of gear is a) 5 m/s.

(b) 45 m/s.

(c) 25 m/s.

(d) 15 m/s.

Q.131 The gears suitable for transmitting the power between two parallel shafts at highspeed are _____. a) spur gears

(b) helical gears

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(c) bevel gears 142

(d) both (a) and (b)

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Q.132 The arrangement used for converting the rotary motion into a linear motion is known as ______. (a) worm gear pair

(b) rack and pinion

(c) linear gears

(d) none of the above

Q.133 The two intersecting axes shafts are connected by the gears known as (a) worm and worm wheel

(b) spiral gears

(c) bevel gears

(d) cone gears

Q.134 The gears used in the differential gear box of automobiles are _____. a) helical gears

b) bevel gear

c) worm gears

d) both (b)and (c)

Q.136 Two non-intersecting and perpendicular axes shafts are connected by ____. a) bevel gears

b) herringbone gears

c) worm and worm wheel

d) both (b)and (c)

Q.137 Which of the following gears are used for high reduction ration? a) Bevel gears

b) Herringbone gears

c) Worm and worm wheel

d) Both (b)and (c)

Q.138 In spur gear pair, the pinion diameter is 200 mm and its speed is 1500 r.p.m. If the gear ration is 4, the gear diameter and its speed are : a) 800 mm and 375 r.p.m. respectively

b) 50 mm and 375 r.p.m. respectively

c) 800 mm and 6000 r.p.m. respectively

d) 50 mm and 6000 r.p.m. respectively.

Q.139 The following data refers to a spur gear pair : Number of teeth on gear = 50, Gear ratio = 2, Pinion speed=1500r.p.m. a) 25 and 3000 r.p.m. respectively

b) 100 and 760 r.p.m. respectively.

c) 100 and 3000 r.p.m. respectively

d) 25 and 750 r.p.m. respectively.

Q.140 In a spur gear pair, the torque on gear shaft is 10 N-m. If the gear ration is 5, the torque on pinion shaft is ______. a) 10 N-m

b) 2N-m

c) 50 N-m

d) 15 N-m

Q.141 In a spur gear pair, the power and torque on pinion shaft are 20 kW and respectively. If the reduction ratio is 2, the power and torque on gear shaft (a) 10 kW and 20 N-m respectively

(b) 40 kW and 80 N-m respectively

(c) 20 kW anD 80 N-m respectively

(d) 20 kW and 20 N-m respectively

Q.142 In a compound gear train, the reduction ratio for first stage is 4 and the reduced ratio for second stage is 3. The overall reduction ratio is______. a) 12

(b) 7

(c) 4

(d) 3

Q.143 Which of the following drive does not need lubrication ? (a) Spur gear drive

(b) Chain drive

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(c) Helical gear drive (d) None of the above 143

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Q.144 The herringbone gears are similar to ________. (a) spur gears

(b) helical gears

(c) bevel gears

(d) worm gears

Q.145 In a gear pair, if the gear and pinion are rotating in a same direction, then it mustbe (a) a herringbone gear pair

(b) a helical gear pair

(c) an internal gear pair

(d) none of the above

Q. 147 In a spur gear pair, the input and output speeds are 1500 r.p.m. and 1000 r.p.m- respectively. Then the following values are feasible: a) Input power = 15 kW and Output power = 10 kW b) Input power = 10 kw and Output power = 15 kw c) Input power = 15 kW and Output power = 15 kW d) None of the above Q.148 In a spur gear pair, the input power and output power are same. If the reduction ratio is 3, then following values are feasible : (a) Input torque = 3 N-m and output torque = 3 N-m. (b) Input torque = 3 N-m and output torque = 1 N-m. (c) Input torque = 1 N-m and output torque = 3 N-m. (d) none of the above.

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CHAPTER 2 ==============================================================================================================================

Answer Key ==================================================================================================================== Q.1

(b)

Q.2

(d)

Q.3

(b)

Q.4

(c)

Q.5

(d)

Q.6

(a)

Q.7

(a)

Q.8

(d)

Q.9

(b)

Q.10 (d)

Q.11 (a)

Q.12 (a)

Q.13 (c)

Q.14 (b)

Q.15 (a)

Q.16 (b)

Q.17 (a)

Q.18 (c)

Q.19 (a)

Q.20 (a)

Q.21 (c)

Q.22 (c)

Q.23 ()

Q.24 (c)

Q.25 (b)

Q.26 (d)

Q.27 (b)

Q.28 (a)

Q.29 (a)

Q.30 (c)

Q.31 ()

Q.32 (d)

Q.33 (c)

Q.34 (a)

Q.35 (c)

Q.36 (c)

Q.37 (b)

Q.38 (c)

Q.39 (b)

Q.40 (b)

Q.41 (c)

Q.42 (d)

Q.43 (c)

Q.44 (a)

Q.45 (c)

Q.46 (b)

Q.47 (b)

Q.48 (d)

Q.49 (b)

Q.50 (b)

Q.51 (a)

Q.52 (c)

Q.53 (b)

Q.54 (a)

Q.55 ()

Q.56 ()

Q.57 (c)

Q.58 (b)

Q.59 (c)

Q.60 (b)

Q.61 (d)

Q.62 (b)

Q.63 (c)

Q64. (a)

Q.65 (b)

Q.66 (d)

Q.67 (a)

Q.68 (b)

Q.69 (a)

Q.70 (d)

Q.71 (b)

Q.72 (c)

Q.73 (a)

Q.74 ()

Q.75 ()

Q.76 (d)

Q.77 (d)

Q.78 (d)

Q.79 (c)

Q.80 (d)

Q.81 (c)

Q.82 (a)

Q.83 (d)

Q.84 (d)

Q.85 (b)

Q.86 (d)

Q.87 (b)

Q.88 (c)

Q.89 (c)

Q.90 (a)

Q.91 (d)

Q.92 (b)

Q.93 (d)

Q.94 (a)

Q.95 (d)

Q.96 (c)

Q.97 (a)

Q.98 (a)

Q.99 (b)

Q.100 (a)

Q.101 (b)

Q.102 (a)

Q.103 (c)

Q.104 (a)

Q.105 (d)

Q.106 (d)

Q.107 (a)

Q.108 (a)

Q.109 (d)

Q.110 ()

Q.111 (a)

Q.112 (c)

Q.113 (d)

Q.114 (b)

Q.115 (c)

Q.116 (a)

Q.117 (d)

Q.118 (c)

Q.119 (c)

Q.120 (d)

Q.121 (d)

Q.122 ()

Q.123 ()

Q.124 ()

Q.125 ()

Q.126 (b)

Q.127 (a)

Q.128 (d)

Q.129 (a)

Q.130 (d)

Q.131 (b)

Q.132 (b)

Q.133 (c)

Q.134 (b)

Q.135 ()

Q.136 (c)

Q.137 (c)

Q.138 (a)

Q.139 (d)

Q.140 (b)

Q.141 (c)

Q.142 (a)

Q.143 (d)

Q.144 (b)

Q.145 (c)

Q.146 ()

Q.147 (c)

Q.148 (c)

=================================================================================================

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UNI T II Design Fundamentals Chapter 3 ========================================================================================= Q.1

In engineering context, the formulation of a plan for the satisfaction of human need is called as _____.

Q.2

(a) design

b) production planning

(c) process planning

d) budgeting

The process of selection of materials, shapes, sizes and arrangements of mechanical elements is known as,

Q.3

(a) product development,

(b) material design

c) material selection

d) none of the above

Machine design does not include a) selection of materials. b) selection of arrangements of mechanical elements. c) selection of shapes and sizes. d) selection of machine.

Q.4

Q. 5

Q.6

Q.7

Q.8

Q.9

Machine design includes (a) material selection

(b) manufacturing of components,

(c) testing of components

(d) all of the above.

The machine design includes (a) selection of materials

(b) selection of sizes and shapes,

(c) selection of arrangements

(d) all

Product needs to be designed for a) functional requirements

(b) appearance.

(c) user comfort

(d) all of the above

The product or system is required to be designed so as to ensure that the prescribed task satisfactorily. It is known as _________

.

(a) design for comfort

(b) design for functional requirement

(c) design for safety

(d) all of the above

_____ is net the step in design process. (a) Synthesis

(b) Interference checking

(c) Analysis of forces

(d) Selection of material

The first step in any design process is a (a) selection of material.

(b) preparation of drawings.

(c) determination of dimensions

(d) definition of problem.

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Q.10

The process of selecting or creating the mechanism for the machine and shapes of the me chanical elements so as to get the desired output for the given a) analysis

Q.11

b) optimization

c) synthesis

(d) creative design

Drawing free body diagram and determination of forces acting on the machine element is part of the step : ____ , in design process.

Q.12

Q.13

Q.14

(a) Preparation of Drawing

(b) Determination of Dimensions

(c) Analysis of Forces

(d) Synthesis

In design procedure, the synthesis is always followed by (a) analysis

(b) selection of material

(c) ergonomics

d) aesthetics

In design procedure, the last step is (a) selection of material.

(b) definition of problem.

(c) preparation of design report

(d) analysis of forces.

Ability of the machine element to avoid the failure due to yielding under load is known as ____. (a) rigidity

b) strength

c) toughness

d) safety

Q. 15 Ability of the machine element to keep the deflections within the permissible under the load is known as _____. a) rigidity

b) strength

c) safety

d) toughness

Q. 16 The objective of ergonomic is ______. a) to make user adopt himself to the machine b) to make machine fit for user c) to make the product economical d) to make the product stronger Q. 17 Stiffness is an important consideration in design of _____. (a) springs

(b) electric switches (c) TV

(d) music system

Q. 18 Ergonomics deals with the a) economy of the product. b) appearance of the product. c) man-machine-working environment relationship. d) safety of the product. Q.19

Ergonomics deals with the (a) user comfort

(b) safety of the product

(c) cost of the product

(d) optimization of product

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Q. 20 The design of a computer chair is a best example of (a) computer aided design

(b) system design

(c) machine design

(d) ergonomic design

Q.21 The design of dash board of a car is an example of (a) optimum design

(b) ergonomic design,

(c) cost effective design

(d) element design.

Q.22 The important area covered under ergonomics is (a) energy expenditure in hand and foot-operations. (b) cost of the material. (c) cost of manufacturing process. (d) both (a) and (b). Q.23

The important area covered under ergonomics is a) Communication between user and machine. b) Human anatomy and posture while using the machine. c) Working environment. d) All of the above.

Q. 24 Any man-machine system has two units : (a) Display and control.

(b) Input and output.

(c) Process and product.

(d) Demand and supply.

Q. 25 Every closed loop type man-machine system essentially has (a) display unit.

(b) control unit,

(c) electric supply,

(d) both (a) and (b)

Q. 26 In a man-machine system, the display unit is used for (a) information reception

(b) machine control.

(c) corrective action

(d) all of above

Q. 27 In a man-machine system, the control unit is used for (a) corrective action

(b) display of information.

(c) controlling the operator

(d) both (a) and (b)

Q. 28 The working environment factor in ergonomic considerations can be : (a) worker salary

(b) other perks

(c) lighting

(d) promotions of worker.

Q. 29 The man-machine closed loop system is influenced by (a) cost of manufacturing

(b) working environment.

(c) material properties.

(d) none of the above.

Q. 30 The appearance of the product is delt by (a) aesthetics

(b) ergonomics

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(c) process planning 148

(d) all of the above.

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Q. 31 Aesthetics deals with the (a) human comfort

(b) human safety

(c) delicacy of the product

(d) none of the above.

Q. 32 The following is an important guideline in aesthetic design. (a) the appearance should contribute to the performance of the product. (b) the appearance should reflect the cost of the product. (c) the product should be comfortable to the user. (d) all of the above. Q.33

Force can be defined as a) stress/area

Q.34

c) stress × area

d) mass × velocity

b) force ×area

c) mass/ area

d) strain / area

Stress is defined as a) force/area

Q.35

b) stress × strain

The stress is defined as a) internal force per unit area at any section b) external force per unit surface area c) surface force per unit surface area

Q.37

The unit of stress is ____. a) N/m2

Q.38

c) 10-6MPa

d) none of the above

b) 106 Pa

c) 103N/m2

d) 10-3 Pa

b) 106N/mm2

c) 10-6N/mm2

d) 10-3N/mm2

b) 10MPa

c) 1Pa

d) none of the above

(b) N/m2

(c) kg/m2

d) Pa/m2

The unit of stress is a) N-m2

Q.43

(b) 103MPa

1N/m2is equal to a) 1MPa

Q.42

d) all of the above

1N/m2is equal to a) 103N/mm2

Q.41

c) MPa

1 N/m2 is equal to a) 1 Pa

Q.40

b) N/mm2

1N/m2 is equal to (a) 106MPa

Q.39

d) all of above

If the deformed length of the body is more than the original length, then it must be subjected to (a) tensile stress

Q.44

(b) compressive stress (c) impact stress

(d) both(a) and (b)

If the body is subjected to compressive stress a) its original length is less than the deformed length. b) its original length is more than deformed length. c) its stress is more than strain. d) both (b) and (c)

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Q.45

Strain is defined as (a) force per unit area

(b) deformation per unit length.

(c) force per unit volume

(d) ability to withstand the load

Q.46 The unit of strain is, (a) N/m2 Q.47

(b) N/m

Unit of strain is _______ (a) unit less

(c) metre

d) none of the above

(c) mm

d) N/mm2

.

(b) meter

Q. 49 Hooke's law states that, a) force is directly proportional to strain

(b) force is directly proportional to stress

(c) stress is directly proportional to strain

(d) stress is inversely proportional to strain

Q. 50 Hooke's law holds good upto a) elastic limit

(b) yield point

(c) proportional limit (d) ultimate strength.

Q. 51 In Hooke's law the constant of proportionality is (a) modulus of elasticity

(b) stress,

(c) strain.

(d) poisson's ratio.

Q. 52 The modulus of elasticity is defined as a) strain/stress

(b) strain x stress

(c) stress /strain

(d) force / area.

(c) N-m2

(d) Pa/m2

c) breaking

(d) fatigue failure

Q. 53 The unit of modulus of elasticity is (a) unit less

(b) N/m2

Q. 54 Brittle material does not show. (a) fracture

(b) yielding

Q. 55 The yield strength is defined as the (a) stress at which stress increases in proportion to strain. (b) stress at which elongation increases without increase in stress. (c) stress at which stress increases without increase in strain. (d) stress at which stress and strain are constant. Q. 56 If the material do not have well defined yield strength, then it must be (a) ductile material

(b) weak material

(c) brittle material

(d) non-ferrous material.

Q. 57 The stress at which strain increases without increase in stress is known as (a) elastic limit.

(b) constant stress

(c) proportional limit (d) yield strength

Q. 58 Brittle material do not have well defined (a) ultimate strength

(b) yield strength.

(c) shear strength

(d) modulus of elasticity

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Q. 60 The unit of modulus of elasticity is same as that of ____. (a) strain Q.61

(b) stiffness

(c) stress

(d) none of the above

(c) GPa

(d) all of the above

The unit of modulus of elasticity is ____. (a) N/mm2

(b) N/m2

Q. 62 Which of the following strengths has maximum value ? (a) elastic limit

(b) proportional limit (c) yield point

(d) ultimate strength

Q. 63 Which of the following strengths has minimum value ? (a) proportional limit (b) elastic limit Q.71

(c) yield point

(d) ultimate strength

The bar of length 100 mm is deformed by 0.1 mm. If the modulus of elasticity of bar is 200 x 109 N/m3 , the stress induced in bar is,

Q.72

(a) 2000 x 109 N/m3

(b) 200 N/mm2

(c) 200x10® N/mm2

(d) 2x108 N/m2

The bar of 100 mm2 cross sectional area is subjected to a tensile force of 10 kN. The tensile stress induced in bar is, (a) 100 N/m2

Q.73

(c) 100 N/mm2

(d) 100 x 106 N/m2

The ratio of material strength to factor of safety is known as (a) yield strength

Q.74

(b) 100 x 103 N/m2

(b) ultimate strength

(c) braking strength

(d) allowable stress

A prime objective of factor of safely is (a) to reduce the cost of the component

(b) to improve the efficiency

(c) to account for uncertainty

(d) both (a)and (c)

Q. 75 The factor of safety can be defined as (a) material strength/working stress

(b) ultimate strength/yield strength

(c) yield strength /material strength

(d) both (a)and (b)

Q. 76 The range of factor of safety can be (a) 1.25 to 4

(b) 20 to 40

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151

(d) less than 0.5

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CHAPTER 3 =============================================================================================================

Answer Key =============================================================================== Q.1

(a)

Q.2

(b)

Q.3

(d)

Q.4

(a)

Q.5

(d)

Q.6

(d)

Q.7

(b)

Q.8

(b)

Q.9

(d)

Q.10 (*)

Q.11 (c)

Q.12 (a)

Q.13 (c)

Q.14 (b)

Q.15 (a)

Q.16 (b)

Q.17 (a)

Q.18 (c)

Q.19 (a)

Q.20 (d)

Q.21 (b)

Q.22 (a)

Q.23 (d)

Q.24 (a)

Q.25 (d)

Q.26 (a)

Q.27 (a)

Q.28 (c)

Q.29 (b)

Q.30 (a)

Q.31 (d)

Q.32 (a)

Q.33 (c)

Q.34 (a)

Q.35 (a)

Q.36 ()

Q.37 (d)

Q.38 (*)

Q.39 (b)

Q.40 (c)

Q.41 (a)

Q.42 (b)

Q.43 (a)

Q.44 (b)

Q.45 (b)

Q.46 (d)

Q.47 (a)

Q.48 ()

Q.49 (c)

Q.50 (c)

Q.51 (a)

Q.52 (c)

Q.53 (b)

Q.54 (b)

Q.55 (b)

Q.56 (c)

Q.57 (d)

Q.58 (b)

Q.59 ()

Q.60 (c)

Q.61 (d)

Q.62 (d)

Q.63 (a)

Q64. ()

Q.65 ()

Q.66 ()

Q.67 ()

Q.68 ()

Q.69 ()

Q.70 ()

Q.71 (b)

Q.72 (d)

Q.73 (d)

Q.74 (c)

Q.75 (a)

Q.76 (a)

======================================================================================

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Chapter 4 =================================================================================================== Q.1

Q.2

Mechanical properties of material are those properties which describe _____. (a) mechanical strength of the material

(b) behaviour of the material under use

(c) fatigue strength of the material

(d) none of the above

_____ of materials are those properties which describe the behaviour of the Material under use.

Q.3

Q.4

a) Physical properties

b) chemical properties

c) mechanical properties

d) strength properties

The ability of material to resist stress without failure, when subjected to a load is known as a) stiffness

b) load carrying capacity

c) strength

d) toughness

The static strength of a material is measured by a) yield strength

Q.5

Q.6

c) fatigue strength

d) both (a)and (b)

The fluctuating load varies in a) magnitude only

b) direction only

c) magnitude and direction both

d) magnitude and/or direction

The graph of load versus is a straight line parallel to time axis. Then it must be a case of a) impact load

Q.7

b) ultimate strength

b) static load

c) fatigue load

d) time dependent load

The ability of a material to resist stress stress without failure, when subjected to fluctuating load is known as a) fatigue strength

Q.9

b)static strength

c) yield strength

d) ultimate strength

The property of material which enables it to regain its original shape after the external load is removed is called as a) ductility

Q.10

b) elasticity

c) malleability

d) resilience

The property of a material which enable it to regain the permanent deformation after external load is removed is called as a) elasticity

Q.11

c) plasticity

d) malleability

The property which is important in forging and press work is a) elasticity

Q.12

b) deformity

b) plasticity

c) stiffness

d) brittleness

The property of elasticity is required in ____. a) forging and stamping

b) press work

c) ornamental work

d) none of the above

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Q.13

The property of plasticity is required in _____. a) forging and stamping

b) press work

c) ornamental work

d) all of the above

Q. 14 The ability of material to resist the deformation under the load is called as' (a) strength

(b) toughness

(c) stiffness

(d) resilience

Q. 15 The property of a material that enables it to be drawn out or elongated is called as (a) ductility

(b) stiffness

(c) plasticity

Q. 16 If the percentage elongation is more than 5%, it is rated as a) ductile Q.17

Q.18

d) rigid material

b) brittle material

c) rigid material

d) high strength material

_____ is an example of ductile material b) Aluminium

c) Copper

d )All of the above

c) Aluminium

d) All of the above

______ is an example of brittle material. b ) Mild steel

The material that shows lack of deformation before rupture is called as A) brittle material

Q.21

c) brittle material

a) ductile material

a) Cast iron Q.20

as

Material with less than 5% elongation is considered as

a) mild steel Q.19

b) elastic material

(d) resillience

b) ductile material

c) weak material

d) rigid material

In ductile material, the failure take place due to a) fracture

b) fatigue

c) yielding

d) wear

Q. 22 In brittle materials, the failure takes place due to (a) fracture.

(b) fatigue

(c) yielding

(d) deformation

Q. 23 Which of the following statements is correct ? a) ductile as well as brittle materials show greater plastic deformation to fracture. b) ductile materials show negligible plastic deformation while brittle! show greater plastic deformation before fracture. c) ductile materials show greater plastic deformation while brittle! show negligible plastic deformation before fracture. d) ductile as well as brittle materials show negligible plastic deftbefore fracture. Q.24

!

The property of material which enables it to undergo change in shape and size without rupture, under external load is called (a) ductility

Q.25

(b) malleability

(c) plasticity

(d) toughness

The property which is important in wire drawing is (a) malleability

(b) plasticity

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(c) ductility 154

(d) resilience

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Q.26

Q.27

The properties which are important in forging and press work are a) malleability and plasticity

b) resilience and elasticity

c) strength and stiffness

d) hardness and ductility

______ is an important property in press work. a) Strength

Q.28

b) Stuffiness

c) Malleability

d) all of the above

Which of the following statement is correct ? a) ductility increases with temperature, while malleability decreases with temperature. b) ductility decreases with temperature, while malleability increases with temperature. c) ductility and malleability increase with temperature. d) ductility and malleability decrease with temperature.

Q. 29 The capacity of material to absorb the elastic strain energy is called a) Toughness Q.31

(b) Resilience

(c) Ductility

(d) Malleability

Resilience is the capacity of a material to (a) absorb energy without fracture

(b) absorb kinetic energy

(c) absorb elastic strain energy

(d) resist deformation

Q. 32 The total energy absorbed per unit volume by the material during its elastic deformation is called as __________. (a) potential energy

(b) kinetic energy

(c) modulus of toughness

(d) modulus of resilience

Q. 33 The area under stress-strain curve in ____ region gives modulus of resilience. (a) elastic

(b) plastic

(c) fracture

(d) elastic and plastic

Q. 34 The property important for mechanical springs is (a) brittleness

(b) resilience

(c) malleability

(d) plasticity

Q. 35 The modulus of resilience is defined as a) the energy absorbed per unit volume of material when loaded to its ultimate limit b) the energy absorbed per unit mass of material when loaded to its elastic limit c) the energy absorbed per unit volume of material when loaded to its elastic limit d) the energy absorbed per unit volume of material when loaded till its fracture Q. 37 The total capacity of the material to absorb energy without fracture is called (a) resilience

(b) malleability

(c) ductility

(d) toughness

Q. 38 The modulus of toughness is defined as (a) the energy absorbed per unit volume of material when loaded till its fracture (b) the energy absorbed per unit volume of material when loaded to its elastic limit (c) the energy absorbed per unit mass of material when loaded to its elastic limit (d) the energy absorbed per unit weight of material when loaded till its fracture. VISION ENGINEERING ACADEMY, PUNE

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Q. 39 The components subjected to impact loads are normally designed for (a) resilience

(b) malleability

(c) toughness

(d) ductility

Q. 41 The total energy absorbed per unit volume by the material before its fracture is called as___. (a) potential energy

(b) modulus of toughness

(c) modulus of resilience

(d) kinetic energy

Q. 42 ______

is essential property for the components subjected to impact loads.

a) Ductility

(b) Hardness

(c) Toughness

(d) Stiffness

Q. 43 The property of a material which enables it to resist penetration or abrasion is called

Q.44

a) toughness

(b) hardness

(c) corrosion resistance

(d) stiffness

________

is an important property for the components subjected to surface stresses

(a) Toughness Q.45

Q.47

(c) Resilience

(d) Hardness

The following property is important for components subjected to surface stresses (a) Creep

Q.46

(b) Strength

(b) Fatigue strength

(c) Hardness

(d) Static strength

The unit of hardness is (a) N/m2

(b) kg/m3

(c) N-m

d) brinell hardness number

Creep is defined as (a) progressive deformation under load. (b) progressive deformation under load at high temperature. (c) progressive deformation under load at sub zero temperate (d) progressive deformation under load at high pressure.

Q.48

At high temperature the creep exists (a) even at stresses below the yield strength (b) at stresses only above the yield strength (c) at stresses above the ultimate strength (d) at stresses above the braking strength

Q.49

The progressive deformation under the load at high temperature is called ______. (a) fatigue

Q.50

(b) creep

(c) slip

(d) failure

The engineering materials are broadly classified as : (a) steel, copper, aluminium and cast iron (b) ferrous alloys and non-ferrous alloys (c) metals and alloys, non-metals and composites (d) metals and alloys

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Q.51

The example of ferrous alloy is _____. (a) plain carbon steel (b) alloy steel

Q.52

Q. 53 _______

(b) carbon

(c) copper

(d) ferric

alloys have iron as their main constituent.

(a) Copper

(b) Metal

(c) Carbon

d) Ferrous

(c)brass

(d) cast iron

(c) steel

d) both (a) and (b)

(c) bronze

(d) all of the above

c) iron and copper

(d) iron and cast steel

The following is not a ferrous material. (a) stainless steel

Q.55

(d) all of the above

Ferrous alloys have _____ as their main constituent. (a) iron

Q.54

(c) cast iron

(b) alloy steel

The example of non-ferrous alloy is _____. (a) brass

(b) bronze

Q. 56 The example of ferrous alloy is ______. (a) cast iron

(b) brass

Q. 57 The cast iron is an alloy of _____ (a) iron and steel

.

(b) iron and carbon

Q. 58 The percentage of iron in cast iron is ______. (a) 93 to 97 %

(b) 86to93%

Q. 59 Cast iron does not contain (a) iron

(c) 80 to 86%

(d) above 98%

______. (b) carbon

(c) silicon

(d) copper

Q. 60 Cast iron is _____. (a) an element

(b) a non-metal

(c) an alloy

(d) a non-ferrous metal

Q. 61 Cast iron is an alloy of a) iron, calcium, silicon and manganese

b) iron, carbon, silicon and manganese

c) iron, steel, silicon and manganese

d) iron, silicon and manganese

Q. 62 The percentage of carbon in cast iron is (a) 17 to 20% Q63

(d) less than 0.5%

(b) silicon

(c) cobalt

(d) manganese

The carbon content is more in (a) alloy steel

Q.65

(c) 1.7 to 4%

The cast iron does not contain A) carbon

Q.64

(b) less than 1.0%

(b) plain carbon steel (c) high carbon steel (d) cast iron

The cast iron also contains ______. a) silicon

(b) manganese

(c) sculpture

(d) all of the above

Q. 66 In cast iron, _________ makes molten iron very fluid. a) high carbon content

(b) high iron content

(c) manganese content

(d) sulphur content

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Q. 67 The molten iron is very fluid due to (a) high silicon content

(b) high manganese content

(c) high cobalt content.

(d) high carbon content

Q. 68 The following is not an advantage of cast iron : (a) High tensile strength

(b) High compressive strength.

(c) High wear resistance

(d) Excellent machinability

Q. 69 _____ can be cast into intricate shape. (a) Alloy steel

(b) Plain carbon steel (c) Cast iron

(d) All of the above

Q. 70 The low cost material has good wear resistance, excellent machinability. Then it must be ________. (a) copper

(b) aluminium

(c) alloy steel

(d) cast iron

(c) Cast iron

(d) Brass

Q. 71 ______ is the cheapest alloy. (a) High carbon steel (b) Alloy steel Q. 72 Cast iron has _____

.

(a) high compressive strength

(b) good wear strength

(c) poor tensile strength

(d) all of the above

Q. 73 Cast iron is a _____. (a) ductile material

(b) malleable material

(c) brittle material

(d) elastic material

Q. 74 Cast iron is poor against ___________

loading.

(a) static

(b) direct

(c) fatigue and impact

(d) all of the above

Q. 75 Tensile strength of cast iron is ______ compressive strength. (a) higher than

(b) lower than

(c) equal to

(d) twice the

Q. 76 Following statement about cast iron is incorrect: (a) It has poor tensile strength

(b) It has poor compressive strength.

(c) It is poor against fatigue loading

(d) It is brittle

Q. 77 Which of the following material is most suited for machine tool beds ? (a) alloy steel

(b) cast iron

(c) high carbon steel

(d) plain carbon steel

Q. 78 The cast iron is used for

Q.79

(a) I.C. engine cylinders

(b) gears

(c) bearing housing

(d) all of the above

______is the most widely used type of cast iron. (a) White cast iron

(b) Grey cast iron

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(c) Alloy cast iron

(d) Ductile cast iron

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Q.80

Q 81

The types of cast iron are : a) grey cast iron and white cast iron

b) black cast iron and white cast iron

c) ductile cast iron and brittle cast iron

d) all of the above

The percentage of iron in plan carbon steel is _____. a) 96 to 99%

b) 90 to 94 %

c) 86 to 90 %

d) 82 to 86%

c) less than 3%

d) less than 0.3%

Q.82 The tow carbon steel contain _______carbon. a) less than 20 % Q.83

The low carbon steel is also called as _____. a) stainless steel

Q.84

Q.88

d) none of the above

b) iron and steel

c) steel and carbon

d) iron and carbon

b) 15 to 20 %

c) 5 to 10 5

d) 2000 percentage

c) more than 10%

d) more than 15%

The high carbon steel contains ____ carbon. a) more than 0.6%

Q.87

c) alloy steel

The percentage of carbon in steel is a) less than 1.7%

Q.86

b) mild steel

Plain carbon steel is an alloy of a) iron and cobalt

Q.85

b) less than 10%

b) more than 6%

The following statement about plain carbon steel is incorrect a) It is ductile

b) It has high tensile strength

c) It has poor were resistance

d) It has poor fatigue strength

The plain carbon steel is _______material. a) brittle

b) ductile

c) weak

d) hard

Q. 89 The plain carbon steel has

Q.90

Q.91

(a) high wear resistance

(b) good damping property

(c) high fatigue strength

(d) all of the above

The following statement about plain carbon steel is incorrect: a) It cannot be cast into intricate shapes

b) It has high tensile strength.

c) It is good in vibration damping

d) It has high fatigue strength.

The plain carbon steel is used for _____. (a) bearing housing

b) machine tool bed

(c) shafts

(d) all of the above

(b) cast iron

(c) babbit

d) all

(c) cast steel

(d) (a) or (b)

Q. 92 The shafts are made of (a) steel

Q .93 The leaf spring can be made of (a) plain carbon steel (b) cast iron Q. 94 Alloying elements are added in steel to (a) reduce the material cost

(b) increase the weight,

(c) improve certain mechanical properties

(d) all of the above.

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Q.95

_______ is added to steel to improve the corrosion resistance. (a) Nickel

(b) Silicon

(c) Chromium

(d) Carbon

Q. 96 Following is not an alloying element in alloy steel: (a) Copper

(b) Vanadium

(c) Tungsten

(d) Nickel

Q. 97 _____ is used as an alloying element is alloy steel. (a) Chromium

(b) Nickel

(c) Vanadium

(d) All of the above

Q. 98 The costlier material from the following materials is _________. (a) grey cast iron

(b) white cast iron

(c) alloy steel

(d) high carbon steel

Q. 99 ______ cannot be cast into intricate shapes. (a) Alloy steel

(b) Grey cast iron

(c) Aluminium alloy (d) Plastic

Q. 100 Alloy steel is used as material for ____ . (a) leaf spring

(b) high tensile bolts (c) turbine blades

(d) all of the above

Q. 101 In stainless steel, the major alloying element is (a) cobalt.

(b) chromium

(c) cast iron

Q. 102 Iron based alloy containing _________ (a) 40 to 50%

(d) tungsten

chromium is called stainless steel.

(b) 2 to 4%

(c) 12 to l4%

(d) 0.3 to 0.6%

Q. 103 Iron based alloy containing at least 12 % chromium is called a) nichrome

b) stainless steel

c) iron-chromium alloy

d) none of the above

Q.104 The advantage of non-ferrous alloy over ferrous alloy is a) High static strength

b) High fatigue strength

c) High corrosion resistance

d) all of the above

Q. 105 The following is a property of non-ferrous alloy : (a) High strength

(b) Low cost

(c) Castability

(d) All of the above

Q. 106 The copper alloy has (a) high thermal conductivity

(b) high electrical conductivity.

(c) excellent bearing properties

(d) all of the above

Q.107 Brassies an alloy of a) copper and tin

b) copper and bronze

c) copper and zinc

d) copper and aluminium

Q. 108 Bronze is an alloy of (a) copper and zinc

(b) copper and brass (c) copper and lead

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(d) copper and tin.

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Q. 109 The following is not a property of brass : (a) High corrosion resistance

(b) High strength.

(c) Low coefficient of friction

(d) Good machinability

Q. 110 The alloy of copper and zinc is called as. (a) brass

(b) bronze

(c) babbit

(d) none of the above

Q. 111 The alloy of copper and tin is called as _______. (a) brass

(b) babbit

(c) white metal

(d) none of the above

Q. 112 _____ is a material used for sliding contact bearing. (a) Alloy steel Q. 113 ______

(b) Aluminum alloy

(c) Brass

(d) Chromium alloy

is the costilest material from the following list :

(a) Brass

(b) Bronze

(c) Copper

(d) Stainless steel

Q. 114 Bronze has (a) high corrosion resistance

(b) low coefficient of friction,

(c) good machinability.

(d) all of the above.

Q. 115 Which of the following is the costliest material ? (a) Plain carbon steel

(b) Cast iron

(c) Brass

(d) Bronze

Q. 116 The journal bearings are made of (a) alloy steel

(b) stainless steel

(c) composite material

(d) bronze

Q. 117 The following statement is correct: a) Brass is costliear than bronze

b) Bronze is costliear than brass

c) Plain carbon steel is costilear than bronze d) Both (a) and (c). Q. 118 The following is not a bearing material: (a) Brass

(b) Bronze

(c) Babbit

(d) Alloy steel

(c) copper

(d) chromium

Q. 119 The alloying element for aluminium is. (a) zinc

(b) carbon

Q. 120 The aluminium is used in engineering applications due to : a) low specific weight, high strength and high stiffness. b) low specific weight, high thermal conductivity and good cast ability. c) high strength, high stiffness and high density. 4d) high fatigue strength, high hardness and high stiffness.

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Q.121 The aluminium has a) low density and good castability. b) low coefficient of friction and good wear resistance. (c) high thermal resistance and poor corrosion resistance. d) all of the above. Q.122 The density of aluminium is ________

.

(a) 7800-8000 kg/m3 (b) 6000-6200 kg/m3 (c) 2700-2900 kg/m3 (d) 276-285 kg/m3 Q. 128 The density of steel is . (a) 7800-8000 kg/m3 (b) 5000-6200 kg/m3 (c) 2700-2900 kg/m3 (d) 275-285 kg/m3 Q. 124 The material used for chain cover and I.C. engine cylinder is (a) cast iron

(b) alloy steel

(c) mild steel

(d) alumina

Q. 125 I.C. engine cylinders are made of: (a) aluminium or cast iron

(b) aluminium or plain carboi

(c) cast iron or plain carbon steel

(d) alloy steel or aluminium

Q. 126 Rivets are made of (a) grey cast iron

(b) copper

(c) bronze

(d) aluminium

(c) Plastic

(d) All of the above

(c) natural rubber

(d) synthetic rubber

(c) maximum 10%

(d) minimum 500%

Q. 127 ______ is a non-metal. (a) Ceramic

(b) Graphite

Q. 128 mV- belts and O-rings are made of : (a) composites

(b) plastics

Q. 129 Rubber is capable of extension of (a) maximum 50%

(b) minimum 200%

Q. 130 The power transmission belts are made of (a) synthetic rubber or leather

(b) plastic or leather,

(c) composites or plastic

(d) none of the above,

Q. 131 ______is used in vulcanization of rubber. (a) Phosphorous

(b) Sulpher

(c) Manganese

(d) both (a)and (b)

(c) elastomer

(d) none of the above

(c) Plastics

d) None of the above

(c) Celluloid

(d) all of the above

(c) Teflon

(d) Durite

Q.132 Natural rubber is a _____ (a) polymer

(b) fibre

Q 133 ____ have self lubricating property. (a) Alloy steels

(b) Rubbers

Q.134 _____ is an example of thermoplastic. (a) Teflon

(b) P.V.C

Q. 135 Following is an example of thermoplast : (a) Epoxy

(b) Bakelite

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Q. 136 The application of thermoplastic is _________ (a) moulded gears

(b) gaskets

.

(c) P.V.C. pipes

(d) all of the above

Q. 137 The plastics have (a) low coefficient of friction

(b) self lubricating properties.

(c) high wear resistance

(d) all of the above.

Q. 138 Following is an example of thermosetting plastic : (a) Epoxy

(b) Bakelite

(c) Durite

(d) All

Q. 139 Polymerization is associated with (a) Thermoplastics.

(b) Thermosetting plastics.

(c) Ceramics.

(d) Both (a) and (b).

Q. 140 Following statement is not an advantage of a plastic : (a) It has better corrosion resistance

(b) It has high strength and rigidly,

(c) It has low coefficient of friction

(d) It has low thermal conductivity.

Q. 141 Which of the following statement is incorrect ? (a) Plastic has poor dimensional stability. (b) Plastic has low coefficient of thermal expansion. (c) Plastic has poor heat resistance. (d) Plastic has low strength. Q.142 _____ do not undergo chemical change or do not become hard with theapplication of heat and pressure. (a) Thermosetsb) Thermoplasts

(c) Rubber

(d) None of the above

Q.143 ______ ran be repeatedly remolded with the application of heat and pressure. (a) Thermoplasts

(b) Thermosets

c) Thermoplasts and thermosets

(d) None of the above

Q.144 _____ is an example of thermoplastic. (a) Epoxy

(b) Bakelite

(c) P.V.C.

(d) None of the above

Q. 145 Thermoplasts a) do not undergo chemical change or do not become hard with the application of heat and pressure. b) first hardens under the heat, but as additional heat and pressure is applied, it becomes soft. c) first softens under the heat, but as additional heat and pressure is applied, it becomes hard. d) under go polymerization. VISION ENGINEERING ACADEMY, PUNE

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Q.146 _______ cannot soften gain on application of heat. (a) Thermoplastics

(b) Rubber

(c) Thermosetting plastics

(d) All of the above

Q. 147 The example of thermosets is ________. (a) epoxy

(b) bakelite

(c) durite

(d) all of the above

Q. 148 The material selection depends upon _______. (a) cost of material

(b) availability of material

(c) material properties

(d) all of the above

Q. 149 _____ is not a mechanical property of material. (a) Static strength Q.150 ______ (a) Weight

(b) Elasticity

(c) Brittleness

(d) Weight

is a mechanical property of a material. (b) Volume

(c) Resilience

(d) All of the above

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CHAPTER 4 =============================================================================================================

Answer Key ============================================================================================================== Q.1

(b)

Q.2

(c)

Q.3

(c)

Q.4

(d)

Q.5

(d)

Q.6

(b)

Q.7

(b)

Q.8

()

Q.9

(b)

Q.10 (c)

Q.11 (b)

Q.12 (d)

Q.13 (d)

Q.14 (c)

Q.15 (a)

Q.16 (a)

Q.17 (b)

Q.18 (d)

Q.19 (a)

Q.20 (a)

Q.21 (c)

Q.22 (a)

Q.23 (c)

Q.24 (b)

Q.25 (c)

Q.26 (a)

Q.27 (c)

Q.28 (b)

Q.29 (*)

Q.30 ()

Q.31 (c)

Q.32 (d)

Q.33 (a)

Q.34 (b)

Q.35 (c)

Q.36 ()

Q.37 (d)

Q.38 (a)

Q.39 (c)

Q.40 ()

Q.41 (b)

Q.42 (c)

Q.43 (b)

Q.44 (d)

Q.45 (c)

Q.46 (d)

Q.47 (b)

Q.48 (a)

Q.49 (b)

Q.50 (c)

Q.51 (d)

Q.52 (a)

Q.53 (d)

Q.54 (c)

Q.55 (d)

Q.56 (a)

Q.57 (b)

Q.58 (a)

Q.59 (d)

Q.60 (c)

Q.61 (b)

Q.62 (c)

Q.63 (c)

Q64. (d)

Q.65 (d)

Q.66 (a)

Q.67 (d)

Q.68 (a)

Q.69 (c)

Q.70 (d)

Q.71 (c)

Q.72 (d)

Q.73 (c)

Q.74 (c)

Q.75 (b)

Q.76 (b)

Q.77 (b)

Q.78 (d)

Q.79 (b)

Q.80 (a)

Q.81 (a)

Q.82 (d)

Q.83 (b)

Q.84 (d)

Q.85 (a)

Q.86 (a)

Q.87 (d)

Q.88 (b)

Q.89 (c)

Q.90 (c)

Q.91 (c)

Q.92 (a)

Q.93 (a)

Q.94 (c)

Q.95 (c)

Q.96 (a)

Q.97 (d)

Q.98 (c)

Q.99 (a)

Q.100 (d)

Q.101 (b)

Q.102 (c)

Q.103 (b)

Q.104 (c)

Q.105 (a)

Q.106 (d)

Q.107 (c)

Q.108 (d)

Q.109 (b)

Q.110 (a)

Q.111 (d)

Q.112 (c)

Q.113 (b)

Q.114 (d)

Q.115 (d)

Q.116 (d)

Q.117 (b)

Q.118 (d)

Q.119 (c)

Q.120 (b)

Q.121 (a)

Q.122 (*)

Q.128 (a)

Q.124 (d)

Q.125 (a)

Q.126 (d)

Q.127 (d)

Q.128 (d)

Q.129 (b)

Q.130 (a)

Q.131 (b)

Q.132 (c)

Q.133 (c)

Q.134 (d)

Q.135 (c)

Q.136 (d)

Q.137 (d)

Q.138 (d)

Q.139 (b)

Q.140 (b)

Q.141 (b)

Q.142 (b)

Q.143 (a)

Q.144 (c)

Q.145 (a)

Q.146 (c)

Q.147 (d)

Q.148 (d)

Q.149 (d)

Q.150 (c)

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Chapter 5 =============================================================================================== Q.1

An element is a (a) rigid body

Q.2

(b) resistant body

(c) free body

(d) strong body

Resistant body is a) capable of transmitting force with no deformation. b) capable of transmitting force with uniform velocity. c) capable of transmitting force with negligible deformation. d) capable of transmitting only motion and not force.

Q. 3

Q. 4

Q. 5

Q. 6

Liquid can be used as a link. (a) Always

(b) Sometimes

(c) Never

(d) Only if density is very high

Rope can (a) always act as a kinematic link

(b) never act as a kinematic link,

(c) sometime act as a kinematic link

(d) always be an element.

A body capable of transmitting a force with negligible deformation is called as ____. (a) resistant body

(b) non-deforming body

(c) deforming body

(d) elastic body

A kinematic link must be a _____. (a) strong body

Q.7

(d) all of the above

(b) element

(c) kinematic pair

(d) all of the above

In I.C engine, ______ is an example of kinematic link. a) cylinder

Q.9

(c) resistant body

Kinematic link is also known as ______. (a) kinematic chain

Q.8

(b) elastic body

b) connecting rod

c) piston

d) all of the above

In I.C engine mechanisms, shown in fig. Q.9 part a is a _______. a) kinematic link

b) kinematic pair

c) tensile link

d) compressive link

Q. 10 Kinematic pair has two links______. (a) fixed together. B) connected together with constrained relative motion, c) connected together without relative motion, d) connected together with free relative motion. Q.11

Two kinematic links which are connected together in such a way that their,relative motion is in a definite direction forms a _________. (a) mechanism

b) kinematic chain

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(c) kinematic pair

(d) structure

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Q. 12 Following is not an example of kinematic pair : (a) Piston and cylinder

(b) Bush and pin

(c) Crank and connecting rod

d) Gear pair

Q. 13 Piston and cylinder form a (a) mechanism Q.14

(c) kinematic pair

(d) structure

If two links are welded to each other, they form (a) kinematic pair

Q.18

(b) machine

(b) kinematic chain

(c) machine

(d) none of the above

A nut and screw (a) can form a kinematic pair

(b) can form non-kinematic pair

(c) can form a structure

(d) can form a chain

Q.19 In a kinematic chain, each link has to be

Q.20

a) a part of only one kinematic pair

b) a part of two kinematic pair

c) a part of three kinematics pairs

d) rigidly fixed to all other links

Any kinematic chain requires at least a) three links

Q 23

b) four links

c) five links

d) two links

Fig Q.23 show a four link arrangement with two links fixed. It forms a _____.

a) Kinematic chain

b) mechanism

c) structure

d) machine

Q.23. There can not be a relative motion between even remaining the links. Hence, it forms a structure. (a) structure Q.25

(d) machine

(b) mechanism

(c) fixed chain

(d) machine

(b) machine

(c) structure

d) all

Every mechanism is a (a) kinematic chain

Q.27

(c) fixed chain

If one of the links of a kinematic chain is .fixed, the arrangement is called as (a) structure

Q.26

(b) mechanism

Mechanism is a kinematic chain with_______. (a) an ability to transmit power

.

(b) four links

c) four links and four kinematic pairs (d) one link fixed Q. 29 Every kinematic chain is _______ (a) not a mechanism Q.30

.

(b) a mechanism

(c) a machine

(d) a structure

Every mechanism is _____. a) not a kinematic chain

b) a kinematic chain

c) a machine

d) a low power machine

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Q.31

An example of a mechanism is a) typewriter

b) I.C engine

c) shaping matching

d) all

Q.32 Following is not an example of mechanism

Q.33

a) typewriter

b) lock

c) P-V diagram indicator of engine

d) shaping machine

Arrangement shown in Fig Q. 33 is _____. a) kinematic chainas well as a mechanism b) not a kinematic chain but only a mechanism c) a kinematic chain but not a mechanism d) a structure as well as a mechanism

Q. 34 Mechanism requires minimum _______ moving links ________ fixed links. (a) 3 and 1

(b) 4 and 1

(c) 4 and zero

(d) 3 and 0

Q. 35 The primary function of mechanism is to

Q.36

(a) transmit the power

(b) absorb the energy

(c) transmit the force

(d) transmit or transform the motion.

The different mechanisms formed by fixing different links of the same kinematic chain are known as _____ (a) machines

Q.37

(b) arrangements

(c) inversions

(d) kinematic chains

In a single kinematic chain, if there are 'n' number of kinematic links. Then ____ number of mechanisms can be formed. (a) 1

(b) n

(c) n-1

(d) n/2

Q.39 Kinematic chain is ____. a) a part of kinematic pair as well as mechanism b) is a part of structure as well as mechanism c) not a part of kinematic pair d) a part of kinematic pair but not a part of mechanism Q.40

Machine is a a) mechanism used for transmitting the power. b) mechanism used for transmitting the motion. c) kinematic chain used for transmitting the motion. d) kinematic chain used for converting the motion from one form to another form.

Q. 41 The machine is defined as follows : (a) Mechanism required to absorb energy. (b) Mechanism required to do some kind of work. (c) Mechanism required to transmit motion. (d) Both (a) and (c). VISION ENGINEERING ACADEMY, PUNE

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Q. 42 The primary function of a machine is to_______. (a) transmit or transform the motion

(b) do work

(c) absorb power

(d) support load

Q. 43 Every mechanism is _________.

Q.46

a) not necessarily a machine

b) a machine

c) is not necessarily a kinematic chain

d) a structure

The example of machine is ___________. (a) I. C. engine

Q.47

Q.48

Q.52

(b) only machine and not mechanism

(c) only mechanism and not machine

(d) only machine and not kinematic chain

The quadric cycle chain is also known as _______.

Q.55

Q.57

(d) none of the above

(b) mechanism

(c) four bar chain

(d) I. C. engine

(a) It has four links

(b) One link is fixed

(c) It satisfies Grashof s law

(d) It is the shortest link.

In a four bar mechanism, the link which can make a complete rotation is called _____. (b) rocker

(c) shaft

(d) (a) or (b)

In a four bar mechanism, the link which can make oscillation is called _________ . (b) rocker

(c) lever

(d) (b) and (c)

Grashof s law is related to (a) slider crank chain

(b) four bar chain

(c) double slider crank chain

(d) both (a) and (b)

The number of inversions of four bar chain are : (a) Two

Q.56

(c) four bar chain

In four bar chain, input link can make a complete rotation if and only if:

(a) crank Q.54

(b) link chain

The Grashof s law is related to_________.

(a) crank Q.53

(d) all of the above

(a) machine as well as mechanism

(a) machine Q.50

(c) shaping machine

I. C. engine is an example of _________.

(a) Roller chain Q.49

(b) hand pump

(b) Three

(c) Five

(d) None of the above

Following is not the inversion of four bar chain : (a) Crank and lever mechanism

(b) Double crank mechanism

(c) Double lever mechanism

(d) Four lever mechanism

The example of four bar mechanism is : a) Crank and slotted lever quick return mechanism b) Coupled wheels of locomotive c) Ackermann steering gear mechanism d) Both (b) and (c)

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Q.58

Q.59

The four bar chain consists of: a) four turning pairs

(b) two sliding and two turning pairs,

c) two turning pairs.

(d) one sliding and three turning pairs.

The example of crank and lever mechanism is : a) Slider crank mechanism

b) Coupled wheels of locomotive.

c) Beam engine mechanism

d) Ackermann steering gear mechanism.

Q. 60 In a crank and lever mechanism, the lever is also called as _____ (a) crank Q.61

(b) rocker

(c) coupler

(d) (b) or (c)

The crank and lever mechanism is an inversion of _____. a) slider crank chain

b) double crank chain

c) double lever chain

d) none of the above

Q. 63 In cranks and lever mechanism, a) the length of rotating link is largest b) the length of oscillating link is smallest. c) the length of rotating link is smallest

d) the length of all links is same.

Q. 64 In a crank and lever mechanism, a) one link is rotating and two links are oscillating. b) two links are rotating and one link is oscillating. c) one link is rotating and three links are oscillating. d) all links are rotating. Q. 65 In double crank mechanism, there are a) two rotating links and two oscillating links. b) two rotating links and one oscillating link. c) three rotating links. d) four rotating links. Q.66 The example of double crank mechanism is :

Q.67

(a) Ackermann steering gear mechanism

b) coupled wheels of locomotive

(c) Beam engine mechanism,

d) both (b)and (c)

The example of double lever mechanism is : (a) Ackermann steering gear mechanism

b) coupled wheels of locomotive

(c) Beam engine mechanism.

D) both (a)and (b)

Q. 68 In double lever mechanism there are (a) four oscillating links.

(b) one rotating link and two oscillating links.

(c) three oscillating links.

(d) four oscillating links.

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Q. 69 Ackermann steering gear mechanism is also known as (a) crank lever mechanism.

(b) double crank mechanism.

(c) crank-lever-crank mechanism.

(d) double lever mechanism.

Q. 70 Ackermann steering gear mechanism consists of (a) three turning pairs.

(b) four turning pairs.

(c) two turning and two sliding pairs.

(d) two turning and one sliding pair.

Q. 72 In Ackermann steering gear mechanism, there are _____ (a) four

(b) six

(c) eight

Q. 73 In Ackermann steering gear mechanism, there are (a) one

links.

(b) two

(d) three

______

(c) three

cranks. (d) no

Q. 74 The slider chain mechanism is used in

Q.76

(a) reciprocating air compressor.

(b) I.C. engine.

(c) gas turbine

(d) both (a) and (b).

The slider crank chain consists of : a) four sliding pairs

b) three sliding pairs

c) one sliding pair and three fixed pairs

d) one sliding pairs and three turning pairs

Q.78 The slider crank mechanism consists of : (a) three links

(b) two links

(c) four links

D) all (a), (b) and (c)

Q. 79 In slider crank mechanism, the connecting rod is a ______. (a) rotating link

(b) oscillating link

(c) fixed link

Q. 80 The slider crank mechanism consists of _____ sliding pairs and (a) 1 and 3

(b) 2 and 2

(c) 4 and 0

(d) sliding link turning pairs. d) 0 and 4

Q. 81 In slider crank mechanism, the crank is _____ link. (a) a sliding Q.83

(b) an oscillatory

(c) a rotary

(d) a fixed

The slider crank mechanism has a) one slider and one crank b) one slider, one crank and one connecting rod c) one slider, one crank, one connecting rod and one cylinder d) two sliders and two cranks

Q.84

In slider crank mechanism, the distance travelled by slider from one end to other end is equal to ____. a) length of crank

b) 2 × length of crank

c) length of connecting rod

d) length of cylinder

Q. 90 Mouse and Mouse pad forms a a) kinematic pair

b) mechanism

VISION ENGINEERING ACADEMY, PUNE

(c) machine 171

(d) none of the above

© VISION ENGINEERING Publications

Q.91

The slider crank mechanism consists of ____ links. (a) 3

(b) 4

(c) 6

(d) 2

(c) mechanism

(d) none of the above

(c) four inversions

(d) infinite inversions.

Q. 92 Door hinges are example of : (a) kinematic pair

(b) structure

Q. 93 A slider crank chain has (a) two inversions Q.94

(b) three inversions

IC engine mechanism is an inversion of a slider crank chain with (a) cylinder fixed

(b) slider fixed

(c) crank fixed

(d) crank shaft fixed

Q. 95 The following is an inversion of slider crank chain : (a) Whitworth quick return mechanism

(b) Hand pump.

(c) Ackermann steering gear mechanism

d) Both (a) and (b).

Q. 96 In Whitworth quick return mechanism, (a) shortest link is fixed

(b) longest link is fixed

(c) slider is fixed.

(d) cylinder is fixed

Q. 97 In crank and slotted lever quick return mechanism,

Q.98

Q.99

(a) shortest link is fixed

(b) longest link is fixed

(c) slider is fixed

(d) cylinder is fixed

In hand pump mechanism, (a) shortest link is fixed.

(b) longest link is fixed.

(c) slider is fixed.

(d) cylinder is fixed,

In hand pump mechanism, a) there is one rotating link

b) there are two rotating links

c) there are three rotating links

d) there is no rotating link

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CHAPTER 5 ====================================================================================================

Answer Key ======================================================================================================= Q.1

(b)

Q.2

(c)

Q.3

(b)

Q.4

(c)

Q.5

(a)

Q.6

(c)

Q.7

(b)

Q.8

(d)

Q.9

(a)

Q.10 (b)

Q.11 (c)

Q.12 (b)

Q.13 (c)

Q.14 (d)

Q.15 ()

Q.16 ()

Q.17 ()

Q.18 (a)

Q.19 (b)

Q.20 (b)

Q.21 ()

Q.22 ()

Q.23 (c)

Q.24 ()

Q.25 (b)

Q.26 (a)

Q.27 (d)

Q.28 ()

Q.29 (a)

Q.30 (b)

Q.31 (a)

Q.32 (d)

Q.33 (a)

Q.34 (a)

Q.35 (d)

Q.36 (c)

Q.37 (b)

Q.38 ()

Q.39 (c)

Q.40 (a)

Q.41 (b)

Q.42 (b)

Q.43 (a)

Q.44 ()

Q.45 ()

Q.46 (d)

Q.47 (a)

Q.48 (c)

Q.49 (c)

Q.50 (c)

Q.51 ()

Q.52 (a)

Q.53 (d)

Q.54 (b)

Q.55 (b)

Q.56 (d)

Q.57 (d)

Q.58 (a)

Q.59 (c)

Q.60 (b)

Q.61 (d)

Q.62 ()

Q.63 (c)

Q64. (a)

Q.65 (b)

Q.66 (b)

Q.67 (a)

Q.68 (c)

Q.69 (d)

Q.70 (b)

Q.71 ()

Q.72 (a)

Q.73 (d)

Q.74 (d)

Q.75 ()

Q.76 (d)

Q.77 ()

Q.78 (c)

Q.79 (b)

Q.80 (a)

Q.81 (c)

Q.82 ()

Q.83 (c)

Q.84 (b)

Q.85 ()

Q.86 ()

Q.87 ()

Q.88 ()

Q.89 ()

Q.90 (d)

Q.91 (b)

Q.92 (a)

Q.93 (c)

Q.94 (a)

Q.95 (d)

Q.96 (a)

Q.97 (b)

Q.98 (c)

Q.99 (d)

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Chapter 6 ======================================================================================= Q.1

The manufacturing process can be defined as the a) process of converting the semi finished product into finished products b) process of converting the raw material into finished products machines. c) process of assembling the components into a product, d) process of creating new product.

Q.2

Q. 3

The process of converting the raw material into finished product using! is called as (a) finishingprocess

(b) metal cutting process

(c) manufacturing process

(d) none of the above

The process in which molten metal is poured into mould of desired sharp as (a) Metal forming

Q. 4

(b) Plastic

c) Copper

(c) Copper alloy

Q.9

(d) All (a), (b) and (c)

(c) Shaft

(d) Ball bearings

The following component cannot be manufactured by casting : a) flywheel

Q.8

(d) Alloy steel

The example of component manufactured by casting is: (a) Machine tool bed (b) Nut

Q.7

(d) Injection moulding

The following material is suitable for casting : (a) Aluminium alloy (b) Cast iron

Q. 6

(c) Casting

The following material is not suitable for casting: a) Aluminium

Q. 5

(b) Metal forging

b) gears

c) machine tool bed

d) connecting rod

The metal forming process is also known as________ (a) deformation process

(b) casting process

(c) metal cutting process

(d) all (a), (b) and (c)

In metal forming process, a) a molten metal issemifinished condition is converted to finished product b) a molten metal is poured into the mould of desired shape. c) a metal in hot or cold condition is plastically deformed into desired shape. d) (b) and (c).

Q.10

The following is not a metal forming process: a) forging

Q.11

c) rolling

d) drawing

(c) forging

(d) all (a), (b) and (c)

The following is a metal forming process (a) casting

Q.12

b) casting

(b) turning

The ______ is an example of a metal forming process. (a) forging

(b) rolling

VISION ENGINEERING ACADEMY, PUNE

(c) drawing 174

(d) all (a), (b) and (c)

© VISION ENGINEERING Publications

Q.13

The following component cannot be manufactured by metal forming process : a) connecting rod

b) machine tool bed

c) I-sections

d) cranckshaft

Q. 14 The example of component manufactured by metal forming process is _____ (a) I-sections

b) connecting rod

(c) crankshaft

d) all (a), (b) and (c)

Q. 15 In metal forming process, a) substantial material is removed from the raw material to convert it to finished product. b) fine material is removed from the semifinished raw material to convert it to finished product c) no material is removed from the raw material d) the removed material can be processed again and reused. Q.16

The following is an example of metal forming process: a) milling

Q.17

b) metal forming

c) metal deformation d) all (a), (b) and (c)

b) grinding

c) turning

d) d) all (a), (b) and (c)

b) shaping

c) milling

d) grinding

b) shaft

c) gear

d) all (a),(b)and (c)

The following component cannot be manufactured by metel cutting process. a) I- sections

Q.23

d) extrusion

The example of a component manufactured by metal cutting process is _____. a) key

Q.22

c) grinding

The _____ is not a metal cutting process. a) turning

Q.21

b) forging

The _____ is a metal cutting process. a) forging

Q.20

d) grinding

The metal cutting process is also known as_____ a) machining

Q.19

c) sharping

The following is an example of metal cutting process: a) drilling

Q.18

b) forging

b) shaft

c) key

d) gear

The surface finishing processes a) remove the significant material b) change the shape of the component c) remove the significant material as well as change the shape of the component d) none of the above

Q.24

The example of surface finishing process is: a) Grinding

Q.25

b) Shaping

c) rolling

d) Both (a)and (b)

Powder metallurgy is a a) heat treatment process

b) process of making powder from metal

c) process of making the component from a powder mix under pressure and hit d) process of coating the component by hot dry powder. VISION ENGINEERING ACADEMY, PUNE

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Q. 26 In powder metallurgy, the process of heating is called as (a) heat treatment

(b) sintering

(c) hot working

(d) none of the above.

(c) surface finishing

(d) metal forming

Q. 27 Sintering is the_______ process. (a) cooling

(b) heating

Q. 28 The example of a component manufactured by powder metallurgy process is_____. (a) cutting tools

b) small gears

(c) bearing bushes

(d) all (a), (b) and (c)

Q. 30 The process used for making car body parts is known as (a) sheet metal working

(b) shaping

(c) turning.

(d) milling

Q. 31 ____

is the metal joining process.

(a) Casting Q. 32 ______

(b) Forging

(c) Welding

(d) All (a), (b) and (c)

(c) Soldering

(d) All (a), (b) and (c)

is the metal joining process.

(a) Welding

(b) Brazing

Q. 33 Which of the following process essentially involves the melting of metal ? (a) casting.

(b) forging.

(c) powder metallurgy(d) heat treatment.

Q. 34 The mould is related to (a) forging process

(b) casting process

(c) sheet metal working

(d) fabrication.

Q. 35 The mould is the a) component obtained by pouring the molten metal. b) cavity which conforms to the shape of the component to be cast. c) boarder of the casting. d) none of the above. Q. 36 In castingprocess the cavity is called as (a) cast Q.37

(b) pattern

(c) mould

(d) drag

The components of intricate shape can be easily manufactured by (a) forging

(b) sheet metal working

(c) casting

(d) grinding

Q. 38 A component obtained by pouring the molten metal into a mould and all win to solidify, is called ______. (a) mould

(b) pattern

(c) casting

Q. 39 A plant where the castings are produced is called ______ (a) machine shop

(b) foundry

(d) cope .

(c) mould shop (d) casting.

Q. 40 _____ is the upper part of the casting flask. a) Drag

(b) Cope

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(c) Mould 176

(d) pattrn

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Q.41

________

lower part of the casting flask

a) Drag

b) cope

c) mould

d) pattern

Q. 42 Cope is the _____. a) mould cavity

b) casting

c) lower part of the casting flask

d) upper part of the casting

Q. 43 Drag is the ____.

Q.44

(a) mould cavity

b) lower part of the casting

(c) upper part of the casting flask

d) pattern

Find the odd term out from the following: (a) Drag

(b) Pull

(c) Cope

(d) Foundry

Q. 45 The place where castings are made is popularly known as (a) furnace Q.46

(b) foundry

(c) forging shop

d) machins

Which of the following statement is incorrect ? a) Casting can produce components of high strength. b) Casting can produce components of intricate shapes. c) Casting produce gas cavities and blow holes inside the compos d) Aluminium components can be produced by casting process.

Q.47

The components of thickness less than 6 mm cannot be manufactured by a) sheet metal working

b) grinding

c) lapping

d) casting

Q, 48 The blow holes and gas cavities are likely to beformed in component in following process (a) forging

(b) sintering

(c) casting

(d) shaping

(c) machining

(d) none of above

(c) shaping

(d) both (a) and (b).

(c) pattern making

(d) pouring of metal

Q. 49 In process, environmental pollution is high. (a) forging

(b) casting

Q. 50 L.C. engine blocks are manufactured by : (a) forging

(b) casting

Q. 51 The first step in mating process is ______. (a) mouldmaking Q.53

(b) core making

In casting process, the pattern is nothing but a) a final component produced b) a mould made from sand c) the replica of a casting used for making the mould d) a design on the component

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Q. 54 The following statement about casting process is correct : a) The pattern is made by using mould. b) The finalcast component is converted to pattern by machiningprocess. c) The mould is made by using pattern. d) The pattern is required only for complicated shapes for comparison. Q.55

In sand casting, the pattern is made from: (a) Sand

Q.56

(b) Clay

(c) Piaster of paris

(d) Wood

The following material cannot be used for pattern: (a) Wood

(b) Plastic

(c) Aluminum

(d) Sand

Q. 57 The process of making the model of a casting used for making a cavity or mould is called as (a) moulding

(b) modeling

(c) pattern making

(d) casting

Q. 58 In casting process, the mould is commonly made from : (a) Sand

(b) Cast iron

(c) Wood

(d) Plastic

Q. 60 In casting, the material used for mouldmaking is_____. (a) cast iron

(b) aluminium

(c) sand

(d) wood

Q. 62 In casting process, the holes or hollow spaces are obtained by using (a) drills

(b) cores

(c) moulds

(d) cavities

Q. 63 The furnace is essential for the following process : (a) Forging

(b) Shaping

(c) Casting

(d) None of the above

(c) casting

d) all of the above.

Q. 64 The molten metal is required in (a) forging

(b) sintering

Q. 65 The terms runner and riser are associated with (a) forging.

(b) machining

(c) shaping

(d) casting.

Q. 66 _____ is a hole cut in a moulded sand to permit the molten metal to rise above the highest point in the casting, (a) Riser Q.67

(d) Basin

b) runner

c) cope

d) pipe

_____ help in escaping of the air, gas and steam form mould cavity. a) ventilator

Q.69

(c) Cavity

From pouring basin, molten metal is carried to the mould cavity through the _____. a) riser

Q.68

(b) Runner

b) ruuner

c) riser

d) both (b)and (c)

The purpose of riser in casting is: a) to carry the molten metal to mould cavity b) to facilitate escaping of air, gas and steam form mould cavity c) to serve as feeder to feed the molten metal into mould cavity to compensate for shrinkage d) both (b)and (c)

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Q.70

In sand casting process, the matel is meted in ____. a) furnace

Q.72

b) boiler

c) oven

d) all of the above

The sequence of steps in casting process is a) core making -mould making __ pattern making b) mould making __core making __ pattern making c) pattern making __mould making __core making d) mould making _ pattern making __core making

Q. 73 The following statement is incorrect: a) The components produced by sand casting have poor dimensional accuracy b) The sand casting can produce extremely thin sections. c) In sand casting, each casting requires one mould. d) The components produced by sand casting have poor surface finish. Q. 74 The following statement is correct: a) The sand casting can produce components with good dimensional accuracy b) The sand casting can produce extremely thin sections. c) The sand casting process requires furnace. d) All (a), (b) and (c). Q. 75 In sand casting, core is made of______. (a) steel

(b) cast iron

(c) wood

(d) none of the above

Q. 76 In metal forming process, the component of desired shape and size is obtains. a) pouring of molten metal in to cavity

b) matching of material

c) elastic deformation of metal

d) plastic deformation of matel

Q. 77 The metal forming process can be carried out on metal, (a) only in hot condition

(b) in hot or cold condition.

(c) only in cold condition

(d) only at subzero temperature.

Q. 78 For metal forming process (a) force is necessary

(b) both force as well as heat are necessary,

(c) heat is necessary

(d) both force as well as heat are not necessar

Q. 79 The example of metal forming process is (a) casting

(b) shaping

(c) forging

(d) both (b) and (c).

Q. 80 The following is not an example of metal forming process (a) Bending

(b) Rolling

(c) Casting

(d) Extrusion

Q. 81 The process performed by blacksmith is known as (a) casting

(b) shaping

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(c) rolling 179

(d) forging

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Q. 82 The forging operation is performed under

Q.83

Q.84

(a) breaking range of material

(b) elastic state of material.

(c) plastic state of material.

(d) molten state of material.

The forging temperature is the temperature at which the material a) melts

b) loses its plastic properties

c) loses its elastic properties

d) becomes red hot

In _____

process, the material is deformed to desired size and shape by the sudden

application of force. (a) casting

(b) forging

(c) metal cutting

Q. 85 The plasticity of material plays important role is_______ a) forging

(b) casting

(d) both (a) and (b)

process.

c) welding

(d) metal cutting

Q. 86 In forging process, the material deforms______. (a) due to fracture

(b) due to melting

(c) without fracture

(d) both (b) and (c)

Q. 87 In ancient days, the implements of war such as : swords, knives, arrows were made by (a) casting process

(b) forging process

(c) shaping process

(d) both (b) and (c)

Q. 88 The forging process requires application of (a) tensile force.

(b) compressive force (c) shear force

Q. 89 In forging process, the force is applied by (a) hand hammer

(b) power hammer

(d) constant force.

______. (c) press

Q. 90 At forging temperature, the material obeys_____

(d) (a), (b) or (c)

.

(a) Hocke's law

(b) law of gravitation

(c) law of plastic flow

(d) Grashof'slaw

Q. 91 The dies are used in (a) forging process

(b) casting process

(c) shaping process

(d) both (a) and (b).

Q. 92 The following material cannot be used for forging: (a) Steel Q.93

b) lower die

c) ram

d) both (b)and (c)

c) crank

d) guide

In forging press ____ is connected to ram. a) upper die

Q.95

(d) Cast iron

In forging press, ___ is fixed. a) upper die

Q.94

(b) Aluminium alloy (c) Copper alloy

b) lower die

The mechanical press is used in _____ operation. a) forging

b) casting

c) matching

d) none of the above

Q.97 The material used for forging process a) must be the brittle material

b) must be the ductile material

c) can be ductile or brittle material

d) must be the ferrous material

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Q.99 The material used for forging are: a) plain carbon steels and alloy steels

b) Aluminium alloys and copper alloys

c) stainless steels

d) all of the above

Q. 100 The material used for forging must possess _____. (a) ductility

(b) brittleness

(c) elasticity

(d) all (a), (b) and (c)

Q. 101 The forging can be used (a) only for brittle materials

(b) only for ductile materials.

(c) only for steel

(d) only for soft material.

Q. 102 The components subjected to impact loads should be manufactured by (a) forging process.

(b) casting process.

(c) powder metallurgy technique

(d) grinding process.

Q. 103 The following process results in improving the strength and toughness (a) Casting

(b) Milling

(c) Forging

(d) Turning

Q. 104 ____ process gives high dimensional accuracy and eliminates requirement ofmachining. (a) Casting Q. 105 ______

(b) Forging

(c) Welding

(d) Both (a) and (b)

process produces components without blow holes and also

increase sendurance strength of the components. (a) Casting

(b) Milling

(c) Welding

(d) Forging

Q.106 The following statement is incorrect: a) the forging process reduces grain size b) the forging process increases the endurance strength of the parts c) the forging process gives high dimensional accuracy d) None of the above Q.109 The limitation of forging operation is: a) ductile materials cannot be forged b) The forging process reduces the grain size c) Complex components with intricate shapes cannot be produced by forging d) All of the above Q. 110 The following statement is correct: (a) Brittle materials cannot be forged. (b) These are no fire lines in forged components. (c) Forged components are cheaper than cast component. (d) All of the above.

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Q. 111 The limitation of forging process is: (a) High initial cost. (b) complex components with intricate shapes cannot be produced. (c) Brittle materials cannot be forged. (d) All (a), (b) and (c). Q. 112 The following I.C. engine part can not be manufactured by forging: (a) Cylinder block

(b) Crankshaft

(c) Connecting rod

(d) Rocker arm

Q.113 The crankshafts, connecting rods and levers are manufactured by ___ process. a) casting

b) forging

c) moulding

d) all of the above

c) connecting rod

d) both (b)and (c)

Q.114 _____ is manufactured by forging process. a) machine tool bed

b) crankshaft

Q.115 The hot forging of material is carried out at a temperature above______ (a) melting temperature

(b) 2000°C to 2500°C

(c) recrystallization temperature

(d) 150°C to 250°C

Q.116 The term recrystallization temperature is related to_____

.

.

(a) forging process

(b) casting process

(c) welding process

(d) all (a), (b) and (c)

Q. 117 The average temperature necessary for hot forging of aluminum alloys is ______. (a) 150°C to 250°C

(b) 350°C to 525°C

(c) 1100°C to 1200°C

(d) 2200°C to 2500°C

Q.118 ______ helps to avoid the oxidation of the metals or their alloys during forgingprocess. (a) Hand forging (c) Hot forging

(b) Isothermal forging (d) Drop forging

Q.119 In hot forging process, a) the strain hardening effect of material is reduced. b) the yield strength of material is increased. c) the ductility of material is reduced. d) both (a) and (b). Q. 120 The hot forging process requires less force and energy due to (a) decrease in ductility (c) melting of material

(b) decrease in yields strength. (d) increase in enthalpy

Q. 121 Following is the advantage of hot forging : (a) Better dimensional accuracy

(b) Reduction of strain hardening effect,

(c) Increase in yield strength

(d) Both (a) and (b).

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Q.122 _____ increases the ductility of material. (a) Cold forging

(b) Hot forging

(c) Casting

(d) Welding

Q.123 The limitation of hot forging is : a) It leads to strain hardening of the metals and its alloys. b) It requires large force and energy. c) It can lead to warping of the workpiece. d) All of the above Q.124 The term isothermal is related to______ (a) casting

(b) machining

. (c) forging

(d) punching

Q.125 In hot forging, the steel is heated to a temperature range of (a) 100-200°C

(b) 300-500°C

(c) 1000-1200°C

(d) 600-700°C

Q.126 Find the incorrect match : a) Hot forging - recrystallization

b) cold forging - no warping of component

c) Hot forging - high force requirement

d) cold forging - strain hardening effect

Q.127 Find the incorrect match : a) cold forging : heavy and powerful machine b) cold forging : good dimensional accuracy c) cold forging : ductility of material increases d) cold forging : no warping of component takes place Q. 128 Find the incorrect match : a) Hot forging- strain hardening effect present b) Hot forging - poor dimensional accuracy c) Hot forging- no residual stresses d) All of the above Q.129 The cold forging of material is carried out at a temperature a) below zero degree Celsius

b) below melting temperature

c) below recrystallization temperature

d) below atmospheric temperature

Q.130 The cold forging gives a) high dimensional accuracy

b) high ductility

c) reduction of strain-hardening effectd) all of above Q. 131 Normally cold forging is carried out at_______

.

(a) temperature below 0°C

(b) temperature below 0°K.

(c) room temperature

(d) temperature below 0°F

Q. 132 ______ is preferred when the maternal is ductile and soft. (a) Hot forging

(b) Cold forging

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(c) Casting 183

(d) Welding

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Q.133 ______ gives high dimensional accuracy. (a) Cold forging

(b) Hot forging(c) Casting

(d) Due open forging

Q. 134 The following operation requires a press. (a) Shaping

(b) Punching

(c) Forging

(d) Both (b) and (c)

Q. 135 Find the correct match (a) casting - air pollution

(b) forging - sound pollution

(c) casting - sound pollution

(d) both (a) and (b)

Q. 136 The limitation of cold forging process is : (a) Poor dimensional accuracy.

(b) Warping of the workpiece.

(c) Requirement of high die force.

(d) All of the above.

Q. 137 The advantage of cold forging process is : (a) Strain hardening is avoided

(b) Requires less die force.

(c) High dimensional accuracy

(d) All of the above.

Q. 140 The process used by blacksmith is______ (a) drop forging

(b) casting

. (c) press forging

(d) none of the above

Q. 141 In drop forging process, the following element is not used : (a) pneumatic cylinder

(b) crucible

(c) Ram

(d) All (a), (b) and (c)

Q. 142 In drop forging process, the high pressure air is used for

_______.

(a) cleaning

(b) cooling

(c) operating pneumatic cylinder

(d) none of the above

Q. 143 In press forging process, the high pressure fluid is used for_____. (a) washing of component

(b) cooling

(c) operating hydraulic cylinder

(d) none of the above

Q. 145 In_________ process, the operation is in horizontal direction. (a) press forging

(b) drop forging

(c) upset forging

(d) all (a), (b) and (c)

Q.146 Upset forging process is similar to____. (a) press forging process

(b) hand forging process

(c) drop forging process

(d) open die forging process

Q.147 Find the incorrect match : (a) Drop forging - hammer

(b) Press forging - horizontal direction

(c) Upset forging - vertical direction

(d) All (a), (b) and (c)

Q.148 Find the correct match : (a) Drop forging - hammer

(b) Press forging - vertical

(c) Upset forging-vertical

(d) All (a), (b) and (c)

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Q. 149 Find the correct match : a) Forging - Large sized components can be manufactured. b) Forging - Used for ductile materials. c) Forging - Components of intricate shape can be manufactured. d) All (a), (b), (c) are correct. Q. 150 Find the correct match : a) Casting - Fiber lines present in cast components. b) Casting - Large sized components can not be manufactured. c) Casting - Poor static and fatigue strength. d) All (a), (b), (c) are correct. Q. 151 The die and punch are used in (a) casting.

(b) shaping.

(c) sheet metal work.

D) both (b)and (c)

Q. 152 Sheet metal working is carried out in______ . (a) foundry

(b) press shop

(c) machine shop

(d) none of the above

Q. 153 ______ is also known as press working. (a) Casting

(b) Moulding

(c) Forging

(d) Sheet metal working

Q. 154 In sheet-metalworking, the thickness of the component varies from ____ a) 0.1 mm to 8 mm

.

(b) 0.5 mm to 50 mm (c) 1 mm to 100 mm (d) 10 mm to 100 mm

Q. 155 In sheet-metal work, die is a a) stationary part with cavity. b) moving part with cavity. c) moving part which enters in the cavity of desired shape. d) piece of metal sheet. Q. 156 In sheet-metal work, punch is (a) stationary part.

(b) moving part without cavity.

(c) moving part with cavity

(d) driving machine.

Q. 157 In sheet-metal working, the stationary part with cavity is known as_____ (a) punch

(b) die

(c) ram

.

(d) guide

Q. 158 In sheet-metal working, the moving part which is driven by ram is known as______ (a) punch

(b) die

(c) crankshaft

Q. 159 In sheet-metal working, there is some clearance between _____ (a) die and punch

(b) punch and ram

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(c) punch and guide

(d) connecting rod . (d) none of the above

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Q. 160 In sheet-metal working, the clearance is kept between punch and die for______ (a) minimizing friction

(b) lubricating oil

(c) thickness of sheet-metal

(d) there is no clearance

Q. 161 In sheet-metal working, die is________

part and punch is_____ part.

(a) moving, stationary

(b) stationary, moving

(c) moving, moving

(d) stationary, stationary

Q. 162 The sheet-metal work is carried out at________ (a) recrystallization

.

(b) melting

temperature.

(c) 100°C

Q. 163 In sheet-metal working, the_________

(d) room

.

(a) rate of production is high

(b) skilled labor is required.

(c) cost of manufacturing is high

(d) all of the above.

Q.164 The sheet-metal components___. a) have high strength

b) are light weight

c) do not have good surface finish

d) all of the above

Q.165 The sheet-metal working process is used for manufacturing _____. a) crankshafts and connecting rods

b) flywheels and levers

c) automobile and aircraft body parts

d) all of the above

Q. 166 The sheet-metal working process is not suitable for manufacturing_____. (a) steelfurniture's

(b) utensils

(c) aircraft body parts (d) shafts

Q. 167 The sheet-metal working processes are classified as : a) sheet-metal shearing and sheet-metal cutting. b) sheet-metal forming and sheet-metal deforming. c) Sheet-metal shearing and sheet-metal forming. d) sheet-metal punching and sheet-metal blanking. Q.168 _______ (a) Drawing

is the sheet-metal shearing process. (b) Coining

(c) Embossing

(d) Lancing

(c) Notching

(d) All (a), (b) and (c)

Q.169 _____ is the sheet-metal forming process. (a) Blanking

(b) Coining

Q.170 From the following, find the odd process out : (a) Lancing

(b) Blanking

(c) Notching

(d) Bending

(c) Drawing

(d) Slitting

Q.171 From the following, find the odd process out: (a) Bending

(b) Forging

Q.172 From the following, find the odd process out : (a) Bending

(b) Milling

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(c) Forging 186

(d) Casting

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Q. 173 In sheet-metal cutting process, the metal cutting is due to______. (a) tension

(b) compression

(c) bending

(d) shear

Q. 174 The operation of producing a hole of any desired shape in a metal sheet using a punch and a die is known as (a) punching

(b) blanking

(c) piercing

Q.175 Piercing is the operation of producing________

(d) lancing

.

a) a circular hole in a metal sheet b) a number of identical holes of any shape in a metal sheet c) a hole of any desired shape in a metal sheet d) a piece of required shape from a metal sheet Q.176 Punching is the operation of producing________

.

a) a circular hole in a metal sheet b) a hole of any desired shape in a metal sheet c) a number of identical holes of any shape in a metal sheet d) a piece of required shape from a metal sheet Q. 177 The operation of producing a hole in a metal sheet using a punch and a die known as (a) blanking

(b) piercing

(c) punching

(d) both (b) and (c)

(c) slitting

(d) notching

Q. 178 Piercing is similar to_______ . (a) blanking

(b) punching

Q. 179 The operation of producing a circular hole in a metal sheet by using a punch a die is known as (a) piercing

(b) blanking

(c) punching.

(d) lancing.

Q. 180 The operation of cutting out a piece of the required shape from a me! using a punch and a die is known as (a) piercing

(b) punching

(c) blanking

Q.181 Blanking is the operation of ________

(d) both (b) and (c)

.

a) cutting the metal-sheet in a straight line b) producing a circular hole in a metal sheet c) cutting out a piece of required shape from a metal sheet d) producing a hole of any desired shape in a metal sheet Q.182 In blanking operation, blank is_____ . (a) a tool used

(b) a machine used

(c) a required component

(d) a hole produced in a metal sheet

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Q.183 The following two operations can be performed simultaneously : (a) punching andpiercing

(b) piercing and blanking

(c) piercing and perforating

(d) none of the above

Q. 184 The operation of producing a number of evenly spaced holes in a metal sheet by using a punch and a die in known as (a) punching

(b) piercing

(c) blanking

(d) perforating

Q. 185 Perforating is the operation of ______. a) producing a single circular hole

b) producing a single hole of any shape

c) producing a number of holes of any shape d) cutting a metal sheet in a straight line Q. 186 ______

produces identical multiple holes.

(a) Punching

(b) Perforating

(c) Piercing

Q. 187 Slitting is the operation of _________

(d) Blanking

.

(a) cutting a small part of metal sheet of desired shape from the edge (b) cutting a metal sheet in a straight line (c) cutting a metal sheet in a circular path (d) cutting a metal sheet into four parts Q. 188 The operation of cutting a metal sheet in a straight line along the length is known as (a) lancing.

(b) slitting

(c) notching

(d) both (a) and (b).

Q. 189 The operation of cutting a part of metal sheet through some portion of its length and then bending the cut portion is known as (a) slitting

(b) notching

(c) lancing

(d) both (b) and (c)

Q. 190 Lancing is the operation of ______. a) cutting a metal sheet in a straight line b) cutting a part of metal sheet through some portion of its length c) removal of small part of a metal sheet of desired shape d) cutting a part of metal sheet through some portion of its length and then bending the cut portion Q.191 The operation of removal of a small part of the metal sheet of the desired shape fro the edge of the metal sheet is known as a) notching

b) lancing

c) slitting

d) perforating

Q.192 Notching is the operation of _____. a) removal of a small part of a metal sheet of desired shape from the edge b) removal of a pieces of the required shape from a metal sheet c) removal of a multiple pieces of the required shape from a metal sheet d) none of the above VISION ENGINEERING ACADEMY, PUNE

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Q.200 Making the hole in metal sheet can be a) blanking

b) punching

c) piercing

d) both(b)and (c)

Q.201 In _____ process, there is no wastage of material. a) punching

b) blanking

c) drawing

d) all of the above

Q.202 In _____ process, there is a wastage of material. a) punching

b) blanking

c) lancing

d) all of the above

Q.203 In ____ process, there is no wastage of material. a) drawing

b) bending

c) squeezing

d) all of the above

Q.204 The following is not a metal shearing process. a) lancing

b) Embossing

c) Notching

d) Blanking

Q. 205 The process of forming a flat metal sheet into a three dimensional hollow shape is known as a) blanking

(b) punching

(c) drawing

(d) forming

(c) blanking

(d) drawig

Q. 206 The metallic cup can be manufactured by (a) punching

(b) piercing

Q. 207 In deep drawing process______. (a) depth of cup < diameter of cup

(b) depth of cup > diameter of cup

(c) depth of cup > 2 x diameter of cup(d) length of wire > diameter of wire Q. 208 In drawing process, pressure pad is used______. a) to apply pressure on die

b) to apply pressure on punch

c) to avoid the possibility of wrinkling

d) to support the blank from the centre

Q. 209 The term spring back is related to __________ operation. (a) drawing

(b) curling

(c) lancing

d) none of the above

Q.210 In bending operation, the metal sheet is stressed beyond ____. (a) elastic limit

(b) plastic limit

(c) ultimate strength

(d) breaking strength

Q. 211 In bending operation, the metal sheet is stressed below______. (a) elastic limit

(b) ultimate strength

(c) tensile strength

Q. 212 In bending operation, the metal sheet is stressed beyond_______

(d) plastic strength but below _____.

a) ultimate strength, elastic limit

b) plastic limit, yield strength

c) elastic limit, ultimate strength

d) ultimate strength, breaking strength

Q.213 The term spring back is related to : (a) Punching

(b) Blanking

(c) Bending

(d) Drawing

Q.214 In a bending process, if the desired bend angle of a component is 40°, the included angle of die should be (a) equal to 40°

(b) less than 40°

VISION ENGINEERING ACADEMY, PUNE

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(d) equal to 80°

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Q. 215 Angles and channels are manufactured by_____ (a) blanking

(b) bending

operation.

(c) drawing

(d) punching

Q. 216 Curling operation is used for manufacturing_________. (a) angles and channels

(b) aircraft and automobile body

(c) vessels, pans and pots

(d) all of the above

Q. 217 In _________ operation, edge of a circular cross-section is formed along a sheet or at the end of a tube. (a) forming

(b) curling

(c) U-bending

(d) deep drawing

(b) blanking

(c) drawing

(d) bending

Q. 218 Curling is a method of (a) forming

Q. 219 The forming process is used for making (a) machine tool bed

(b) gear box housing

(c) automobile body part

(d) both (b) and (c)

Q. 220 _______ is a process of shaping a flat metal sheet into a surface of desired profile. (a) Forming

(b) Curling

(c) Deep drawing

(d) All of the above

Q. 221 ____ is the process of cold squeezing of metal in which all the surfaces are confined within a set of dies. (a) Embossing

(b) Coining

(c) Forming

(d) Profiling

Q. 222 The medals can be manufactured by sheet metal working process known as (a) coining.

(b) forming

c) drawing

(d) blanking.

(c) squeezing

(d) drawing

Q. 223 Coining is also known as __________ . (a) embossing

(b) punching

Q. 224 Squeezing operation is used for manufacturing (a) tooth paste tubes

(b) metal-sheets

______.

c) medals and badges (d) all of the above

Q. 225 The nameplates can be manufactured by the process known as (a) coining

(b) forming

(c) blanking

(d) embossing

Q. 226 ________ is the process of producing the depressed or raised impression of letters,figures or designs on metal sheet. (a) Coining

(b) Squeezing

(c) Printing

(d) Embossing

Q.232 For wire drawing process, the material must have a) high strength

b) good ductility

c) good malleability d) both (b)and (c)

Q.233 the wire drawing process is due to a) elastic flow of metal

b) squeezing of metal

c) plastic flow of metal

d) both (b)and(c)

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Q.234 In ____ process, the metal rod is pulled through a die. a) deep drawing

b) forming

c) wire drawing

d) cupping

Q.236 In welding process, the essential elements is /are : (a) Filler material

(b) Pressure

(c) Heat

(d) Both (a) and (c)

Q.237 In welding process, the heat is required for (a) fusing the filler material.

(b) fusing the metallic parts to be joined.

(c) clearing the surface.

(d) all (a), (b) and (c).

Q, 238 In welding process, the heat required for fusing the two parts can be obtained from: (a) electric energy.

(b) combustion of gases.

(c) chemical reaction.

(d) (a), (b) or (c)

Q. 239 Which of the following statement is incorrect ? a) Welded joint has a strength equal to that of the material being joined. b) Welding can produce fluid tight joint. c) Welded joints are strong against vibrations. d) Welding gives light weight construction. Q. 240 Which of the following statement is correct ? a) Filler material is essential input element in welding process. b) Application of pressure is essential in welding process. c) Welding can produce fluid tight joints, d) all of the above Q. 241 Welding results in____ . (a) distortion of workpiece

(b) residual stresses

(c) harmful radiations

d) all of the above

Q. 242 The welding is used in _______. a) manufacturing of crankshaft

b) manufacturing of engine cylinder

c) manufacturing of boilers, pressure vessels d) all of the above Q. 243 The welding is used in________. a) fabrication of bridges, electric towers b) manufacturing automobile bodies and aircraft bodies c) manufacturing of storage tanks, pipe lines d) all of the above Q. 244 Pressure welding is also known as (a) plastic welding

(b) fusion welding

(c) non-plastic welding

(d) gas welding.

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Q. 245 Fusion welding is a (a) pressure welding.

(b) non-pressure welding,

(c) plastic welding.

(d) spot welding.

Q.246 Welding processes are broadly classified as : a) Pressure welding and Plastic welding

b) Plastic welding and Fusion welding.

c) Gas welding and Electric arc welding

d) All of the above

Q.247 Pressure welding process _______filler material, while non-pressure welding process____ filler material. (a) does not require, requires

(b) requires, requires

(c) does not require, does not require

(d) requires, does not require

Q.248 Plastic welding_______

pressure, while fusion welding_______

pressure.

(a) does not require, requires

(b) does not require, does not require

(c) requires, does not require

(d) requires, requires

Q.249 In_____

Welding process, the two metal parts to be joined are heated and forced

together by an external pressure to make the joint. (a) plastic

(b) fusion

(c) electric are

(d) all of the above

Q. 250 ______ is a type of pressure welding. (a) Forge welding

(b) Electric resistance welding

(c) Pressure thermite welding

(d) All of the above

Q. 251 ______

is a type of non-pressure welding.

(a) Electric resistance welding

(b) electric arc welding

(c) Gras welding

(d) Both (b) and (c)

Q.252 In_________ welding process, the two metal parts to be joined are heated and allowed to solidify to make the joint, without application of external pressure. (a) plastic

(b) fusion

(c) electric arc

(d) both (b) and (c)

Q. 253 Electric arc welding is a type of (a) pressure welding

(b) plastic welding

(c) non-pressure welding

(d) spot welding.

Q. 254 Electric arc welding is a type of _____. (a) fusion welding

(b) non-pressure welding

(c) plastic welding

(d) both (a) and (b)

Q. 255 Electric arc welding requires________ . a) Filler material and external pressure b) Filler material and not external pressure c) neither filler material nor external pressure d) external pressure and not filler material VISION ENGINEERING ACADEMY, PUNE

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Q. 256 Electric arc welding requires a power source with (a) high voltage and high current

(b) low voltage and high current

(c) low voltage and low current

(d) high voltage and low current

Q. 257 In electric arc welding, the voltage range of power source is (a)220-240 V

(b) 20 - 40 V

(c) 420 - 440 V

(d) 2-4V

Q. 258 In electric arc welding, the current requirement is (a) 200 - 500 mA

(b) 1 - 2 A

(c) 5 -10 A

(d) above 100 A

Q.259 In electric are welding using D.C. supply, a) positive terminal is attached to one work pieces and negative terminal other work piece b) positive terminal is attached to electrode and negative terming piece, c) positive terminal is attached to work piece and negative terminal electrode. d) (b) or (c). Q. 260 The most widely used type of welding is (a) gas welding

____. (b) electric arc welding

(c) electric resistance welding

(d) (a) and (b)

Q. 261 Tungsten Inert Gas (TIG) welding is a type of (a) gas welding

(b) electric arc welding

(c) spot

(d) MIG welding

Q. 262 TIG welding means : (a) Titanium inert gas welding

(b) Titanium iron gas welding

(c) Tungsten inert gas welding

(d) Thermal inert gas welding

Q. 263 MIG welding means (a) Molybdenum inert gas welding

(b) Metal iron gas welding

(c) Magnesium inert gas welding

(d) Metal inert gas welding

Q.264 ______ is a type of electric arc welding. (a) TIG welding

(b) MIG welding

(c) SMAW

(d) All of the above

Q. 265 The following are electric arc welding processes : a) Tig and MIG welding

b) Spot and seam welding.

c) Electric resistance and thermal welding

d) Both (b) and (c).

Q.266 In electric arc welding, the temperature produced is in the range of (a) 200 - 400°C

(b) 400 - 800°C

(c) 100 - 150°C

(d) above 160

Q.269 TIG and MIG welding uses____. (a) Carbon dioxide gas cylinder

(b) oxygen gas cylinder

(c) hydrogen gas cylinder

(d) (b) and (c)

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Q. 270 In TIG welding process tungsten electrode is_______

.

(a) used as filer material

(b) consumable type

(c) non-consumable type

(d) both (a) and (b)

Q. 271 In MIG welding process, metal electrode is_________

.

(a) used as filler material

(b) non-consumable type

(c) used as base material

(d) both (b) and (c)

Q. 272 In TIG and MIG welding, gas is used for

____.

a) combustion purpose b) protecting the molten metal from atmospheric contaminants c) cooling the electrode d) both (b) and (c) Q. 273 In _________ welding process, electrode acts are filler material. (a) MIG

(b) TIG

(c) forge

(d) both (a) and (b)

Q. 274 In _________ welding process, separate filler material is used. (a) MIG

(b) TIG

(c) forge

(d) both (a) and (b)

Q. 275 In brazing, the workpieces are heated to a temperature a) equal to melting temperature of the work pieces. b) above 450°C but below the melting temperature of the work pieces. c) equal to 450°C. d) below 450°C. Q. 276 The filler materials used in brazing can be (a) steel

(b) cast iron

(c) copper alloy

(d) none of the above

Q. 277 The following material cannot be used as filler material in brazing : (a) Copper

(b) Silver

(c) Nickel

(d) Steel

Q. 278 The following statement about brazing is incorrect. a) The brazing can join a large variety of dissimilar metals. b) The brazing can join non-metals. c) The strength of brazed joint is higher than that of welded joint. d) The brazing can produce pressure tight joints. Q. 279 The carbide tips can be joined to mild steel shanks in cutting tools by________ (a) electric arc welding

(b) brazing

(c) soldering

(d) gas welding

.

Q. 280 The application of brazing is________. (a) joining of electric wires

(b) fabrication of heat exchanges, pipe fittings

(c) fabrication of steel furniture's

(d) both (a) and (b)

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Q. 281 In soldering, the workpieces are heated to a temperature a) above 450o C

b) equal to 450oC

c) equal to a melting point of workpieces

d) below 450o C

Q.282 The commonly used filler material for soldering is a) tin-lead alloy

b) copper alloy

c) alloy steel

d) both (b)and (c)

Q.283 For joining the components in electric circuit, a) soldiering or brazing can be used

b) soldering can be used

c) soldering or welding can be used

d) brazing can be used

Q.285 The joint has least strength and poor surface finish, then it must have been must by ____ process. A) soldering

b) brazing

c) welding

d) all (a),(b) and (c)

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CHAPTER 6 ==============================================================================================================

Answer Key ================================================================================================= Q.1

(b)

Q.2

(c)

Q.3

(c)

Q.4

(d)

Q.5

(d)

Q.6

(a)

Q.7

(d)

Q.8

(a)

Q.9

(c)

Q.10 (b)

Q.11 (c)

Q.12 (d)

Q.13 (b)

Q.14 (d)

Q.15 (c)

Q.16 (b)

Q.17 (a)

Q.18 (a)

Q.19 (*)

Q.20 (d)

Q.21 (d)

Q.22 (a)

Q.23 (d)

Q.24 (a)

Q.25 (c)

Q.26 (b)

Q.27 (b)

Q.28 (d)

Q.29 ()

Q.30 (a)

Q.31 (c)

Q.32 (d)

Q.33 (a)

Q.34 (b)

Q.35 (b)

Q.36 (*)

Q.37 (c)

Q.38 (c)

Q.39 (b)

Q.40 (*)

Q.41 (a)

Q.42 (d)

Q.43 (b)

Q.44 (b)

Q.45 (b)

Q.46 (a)

Q.47 (d)

Q.48 (c)

Q.49 (b)

Q.50 (b)

Q.51 (c)

Q.52 ()

Q.53 (c)

Q.54 (c)

Q.55 (d)

Q.56 (d)

Q.57 (c)

Q.58 (a)

Q.59 ()

Q.60 (c)

Q.61 ()

Q.62 (b)

Q.63 (c)

Q64. (c)

Q.65 (d)

Q.66 (a)

Q.67 (b)

Q.68 (c)

Q.69 (d)

Q.70 (a)

Q.71 ()

Q.72 (c)

Q.73 (b)

Q.74 (c)

Q.75 (d)

Q.76 (d)

Q.77 (b)

Q.78 (a)

Q.79 (c)

Q.80 (c)

Q.81 (d)

Q.82 (c)

Q.83 (c)

Q.84 (b)

Q.85 (a)

Q.86 (c)

Q.87 (b)

Q.88 (b)

Q.89 (d)

Q.90 (c)

Q.91 (a)

Q.92 (d)

Q.93 (b)

Q.94 (a)

Q.95 (a)

Q.96 ()

Q.97 (b)

Q.98 ()

Q.99 (d)

Q.100 (a)

Q.101 (b)

Q.102 (a)

Q.103 (c)

Q.104 (b)

Q.105 (d)

Q.106 (d)

Q.107 ()

Q.108 ()

Q.109 (c)

Q.110 (a)

Q.111 (d)

Q.112 (a)

Q.113 (b)

Q.114 (d)

Q.115 (c)

Q.116 (a)

Q.117 (b)

Q.118 (b)

Q.119 (a)

Q.120 (b)

Q.121 (b)

Q.122 (b)

Q.123 (c)

Q.124 (c)

Q.125 (c)

Q.126 (c)

Q.127 (c)

Q.128 (a)

Q.129 (c)

Q.130 (a)

Q.131 (c)

Q.132 (b)

Q.133 (a)

Q.134 (d)

Q.135 (d)

Q.136 (c)

Q.137 (c)

Q.138 ()

Q.139 ()

Q.140 (d)

Q.141 (b)

Q.142 (c)

Q.143 (c)

Q.144 ()

Q.145 (c)

Q.146 (a)

Q.147 (d)

Q.148 (b)

Q.149 (b)

Q.150 (c)

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Q.151 (c)

Q.152 (b)

Q.153 (d)

Q.154 (a)

Q.155 (a)

Q.156 (b)

Q.157 (b)

Q.158 (a)

Q.159 (a)

Q.160 (c)

Q.161 (b)

Q.162 (d)

Q.163 (a)

Q.164 (b)

Q.165 (c)

Q.166 (d)

Q.167 (c)

Q.168 (d)

Q.169 (b)

Q.170 (d)

Q.171 (b)

Q.172 (a)

Q.173 (d)

Q.174 (c)

Q.175 (c)

Q.176 (a)

Q.177 (d)

Q.178 (b)

Q.179 (c)

Q.180 (c)

Q.181 (c)

Q.182 (*)

Q.183 (b)

Q.184 (d)

Q.185 (c)

Q.186 (b)

Q.187 (b)

Q.188 (b)

Q.189 (c)

Q.190 (d)

Q.191 (a)

Q.192 (a)

Q.193 ()

Q.194 ()

Q.195 ()

Q.196 ()

Q.197 ()

Q.198 ()

Q.199 ()

Q.200 (d)

Q.201 (c)

Q.202 (d)

Q.203 (d)

Q.204 (b)

Q.205 (c)

Q.206 (d)

Q.207 (b)

Q.208 (c)

Q.209 (d)

Q.210 (a)

Q.211 (b)

Q.212 (c)

Q.213 (c)

Q.214 (b)

Q.215 (b)

Q.216 (c)

Q.217 (b)

Q.218 (d)

Q.219 (c)

Q.220 (a)

Q.221 (b)

Q.222 (a)

Q.223 (c)

Q.224 (c)

Q.225 (d)

Q.226 (d)

Q.227 ()

Q.228 ()

Q.229 ()

Q.230 ()

Q.231 ()

Q.232 (b)

Q.233 (c)

Q.234 (c)

Q.235 ()

Q.236 (c)

Q.237 (b)

Q.238 (d)

Q.239 (c)

Q.240 (c)

Q.241 (d)

Q.242 (c)

Q.243 (d)

Q.244 (a)

Q.245 (b)

Q.246 (b)

Q.247 (a)

Q.248 (c)

Q.249 (a)

Q.250 (d)

Q.251 (d)

Q.252 (d)

Q.253 (c)

Q.254 (d)

Q.255 (d)

Q.256 (b)

Q.257 (b)

Q.258 (d)

Q.259 (c)

Q.260 (b)

Q.261 (b)

Q.262 (c)

Q.263 (d)

Q.264 (d)

Q.265 (a)

Q.266 (d)

Q.267 ()

Q.268 ()

Q.269 (a)

Q.270 (c)

Q.271 (a)

Q.272 (d)

Q.273 (a)

Q.274 (b)

Q.275 (c)

Q.276 (c)

Q.277 (d)

Q.278 (c)

Q.279 (b)

Q.280 (b)

Q.281 (d)

Q.282 (a)

Q.283 (b)

Q.284 ()

Q.285 (a)

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Chapter 7 =================================================================================================== Q. 1

The process of removing the material from the workpiece, in the form of chips, by means of cutting tools so as to give the desired shape and size to the component is called_____. (a) metal forming

Q. 2

Q. 4 Q.5

(c) machining

(d) (a) or (b)

______ is an example of metal cutting process. (a) Milling

Q. 3

(b) surface finishing (b) Grinding

(c) Casting

(d) All (a), (b) and (c)

_____ is an example of surface finishing process. (a) Shaping

(b) Grinding

Lapping is a_____

process.

(a) metal forming

(b) machining

In surface finishing process,_____

(c) Turning

(d) All (a), (b) and (c)

(c) surface finishing

(d) metal cutting

.

a) there is substantial material removal b) there is no material removal c) there is negligible material removal d) there is substantial material removal as well as surface coating Q. 6

The following is a metal cutting process : (a) Shaping

Q. 7

(b) Grinding

(c) Honing

(d) Lapping

The machines used for carrying out metal cutting processes and surface finishing processes are called

Q. 8

(a) Manufacturing machines

(b) Machine tools.

(c) Processing tools

(d) Cutting tools.

The machine tools are used for ________. (a) metal forming

Q. 9

(b) metal cutting

(c) surface finishing

(d) both (b) and (c)

The machine tools are broadly classified as : a) metal machine tools and non-metal machine tools. b) metal cutting machine tools and surface finishing machine tools. c) lathe machines and drilling machines. d) both (a) and (b).

Q. 10 The machine tool used for removing the material from the cylindrical surface is known as (a) shaping machine

(b) milling machine

(c) lathe machine

(d) both (b) and (c).

Q. 11 In a turning machine, the cutting tool a) is stationary while the workpiece moves along its axis. b) moves parallel to the axis of rotation of workpiece. c) moves perpendicular to the axis of rotation of workpiece. d) both (b) and (c). VISION ENGINEERING ACADEMY, PUNE

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Q. 12 The lathe machine is also known as______ (a) shaping machine

(b) surfacing machine (c) turning machine

(d) none of the above

Q. 13 Lathe machine produces______. (a) spherical surface

(b) cylindrical surface

(c) flat surface

(d) both (b) and (c)

Q. 14 In lathe machine, in order to produce cylindrical surface, the cutting tool must a) move perpendicular to the axis of rotation b) move parallel to the axis of rotation c)move along the circumference of the surface d) be stationary Q. 15 In lathe machine, in order to produce flat surface, the cutting tool must_____. a) move perpendicular to the axis of rotation b) move parallel to the axis of rotation c) move in vertical direction d) be stationary Q.18

Q.19

In lathe machine, the tool has a) One type of motion

b) two types of motions

c) Three types of motions

d) no motions

In lathe machine, the mechanism used for mechanized movements of the carried is known as a) saddle

Q.20

d) compound rest

b) saddle

c) apron

d) cross-slide

c) Column

d) Lead screw

c) Carriage

d) all (a) ,(b)and (c)

_______ is not a part of lathe machine. a) Bed

Q.22

c) cross-slide

In lathe machine, the arrangement used for facilitating the taper turning is known as a) compound rest

Q.21

b) apron

b) Carriage

______ is a part of lathe machine. a) Headstock

b) Tailstock

Q. 23 In lathe machine, the function of bed is to (a) provide sliding surface for carriage

(b) provide sliding surface for tailstock.

(c) support tailstock

(d) all (a), (b) and (c).

Q. 24 In lathe machine, the heads took. (a) support the carriage

(b) supports the tailstock

(c) supports the spindle

(d) all (a), (b) and (c)

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Q. 25 In lathe machine, the function of main drive is to (a) drive an electric motor.

(b) drive the spindle.

(c) to change the spindle speed.

(d) both (b) and (c).

Q. 26 In lathe machine, the chuck is mounted on (a) carriage Q.27

Q.28

(b) spindle

(c) tailstock

(d) apron

In lathe machine, the function of chuck is to (a) hold the workpiece

(b) hold the tool.

(c) support the tailstock

(d) change the speed,

In lathe machine, the function of headstock is_______

.

(a) to support the spindle

(b) to house the main drive

(c) to support the tool

(d) both (a) and (b)

Q. 29 In centre lathe, the gearbox or cone pulley is located in (a) carriage Q.30

Q.31

(b) bed

(c) headstock.

(d) tailstock.

Spindle in a lathe machine is a ,_____. (a) solid stationary shaft

(b) hollow stationary shaft

(c) hollow rotating shaft

(d) solid rotating shaft

In lathe machine, the function of tailstock is ________ . (a) to support lead screw

(b) to hole the dead centre

(c) to hold the drill or reamer

(d) both (b) and (c)

Q. 32 In lathe machine, the function of tailstock is to (a) support the spindle

(b) hold the main drive.

(c) hold the dead centre

(d) both (b) and (c)

Q. 33 In lathe machine, the tools like drill and reamer are hold by (a) tool post

(b) headstock

(c) spindle

(d) tail stock

Q. 34 In lathe machine, the dead centre is supported by_______. (a) chuck Q.35

(b) spindle

(c) tail stock

(d) carriage

In lathe machine, the maximum diameter of workpiece that can revolve between the centres is called _______.

Q.36

Q.37

(a) diameter

(b) swing

(c) limiting dimension

(d) height

In lathe machine, the function of carriage is ________. (a) to hold the cutting tool

(b) to give longitudinal feed to cutting tool

(c) to give cross feed to cutting tool

(d) all (a), (b) and (c)

In lathe machine, saddle is the part of _________. (a) compound rest

(b) carriage

VISION ENGINEERING ACADEMY, PUNE

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(d) feed drive

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Q. 38 In lathe machine, the function of carriage is to (a) support the spindle

(b) hold and give feed to cutting tool,

(c) to hold the dead centre

(d) both (b) and (c).

Q. 39 In lathe machine, a) tail stock is located between headstock and carriage. b) headstock is located between tails tock and carriage. c) carriage is located between headstock and tailstock. d) spindle is located between bed and carriage. Q. 40 In lathe machine, the carriage has (a) rotary motion.

(b) longitudinal motion and cross feed,

(c) longitudinal motion.

(d) cross feed.

Q. 41 The 'Swing' of lathe machine is a) the maximum diameter of the workpiece that can be machined. b) the maximum length of the workpiece that can be machined. c) the maximum taper of the workpiece that can be machined. d) the maximum permissible misalignment. Q. 42 In lathe machine, the function of lead screw is_______. a) to give mechanized motion to carriage

b) to give mechanized motion to spindle

c) to give mechanized motion to feed drive

d) all (a), (b) and (c)

Q. 43 In lathe machine, the component which helps in thread cutting is known as (a) cross-slide

(b) compound rest

(c) apron

(d) lead screw

Q. 44 In lathe machine, the component used for engagement and disengagement of lead screw is known as (a) apron

(b) cross-slide

(c) split nut

(d) drive nut

Q. 46 The function of lead screw arrangement in lathe is________. a) to convert the rotary motion of spindle into linear motion of the lead screw. b) to convert the rotary motion of the lead screw into linear motion of the split nut. c) to convert the rotary motion of the split nut into linear motion of the lead screw. d) to support the carriage. Q.46

In lathe machine, the function of feed drive is _______

.

a) transmitting the motion from the main drive to the spindle b) transmitting the motion from the main drive to the lead screw c) transmitting the motion from headstock to the spindle d) both (a) and (b) VISION ENGINEERING ACADEMY, PUNE

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Q.47 In lathe machine, the feed drive is place between

Q.48

(a) headstock and tailstock

(b) tailstock and carriage.

(c) toolpost and tailstock

(d) main drive and lead screw.

In lathe machine, the unit used for transmitting the motion from the main drive to the lead screw is known as (a) apron

Q.49

(b) feed drive

(c) electric motor

(d) gear box

In lathe machine, the following is the correct sequence of elements: a) Feed drive-lead screw-split nut-saddle b) Head stock-lead screw-split nut-feed drive c) Head stock-tail stock-lead screw-feed drive d) Head stock-tail stock-saddle-feed drive.

Q. 50 The following parameter cannot be used for specifying the lathe matching. (a) Swing

(b) Distance between centers

(c) Height of lathe

(d) Overall length of bed

Q. 51 The following parameter is one of the specification parameter for the lathe : (a) Height of lathe

(b) Width of lathe

(c) Swing

(d) All(a),(b) and (c)

Q. 52 The following parameter is used as the specification parameter for lathe: (a) Swing

(b) Distance between centres

(c) Overall length of bed

(d) All (a), (b) and (c)

Q. 53 The following parameter is not the specification parameter for lathe: (a) feedrate

(b) maximum spindle speed.

(c) minimum spindle speed

(d) swing

Q. 55 The following operation cannot be performed on lathe machine: (a) Drilling

(b) Milling

Q. 56 In lathe machine, ______

(c) Boring

(d) All

is the process of removing the material from cylindrical sur

face of the workpiece to reduce its diameter. (a) facing

(b) cylindrical surfacing

(c) turning

(d) machining

Q. 57 Eccentric turning on lathe requires (a) two jaw chuck

(b) three jaw chuck

(c) four jaw chuck

(d) eccentric chuck

Q. 58 In lathe machine, the axis of workpiece is offset from the axis of the lathe spindle during (a) turning

(b) facing

(c) taper turning

(d) eccentric turning

Q. 59 In lathe machine, the tool motion is perpendicular to the axis of the lathe spindle during (a) perpendicular turning

(b) taper turning.

(c) facing.

(d) finishing.

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Q. 60 In lathe machine,_____

is the process of removing the material from the endsurface

of workpiece. (a) turning

(b) end surfacing

Q. 61 In lathe machine, _____ (a) beveling

(c) end turning

(d) facing

is the process of beveling the sharp ends of aworkpiece..

(b) end turning

(c) chamfering

(d) none of the above

Q. 62 The chamfering helps in a) material saving. b) avoiding the injuries to the persons handling the finished product. c) giving aesthetic look to the finished product. d) both (b) and (c). Q. 63 The process of cutting a workpiece into two parts on lathe machine is called as (a) grooving

(b) slitting

Q. 64 In lathe machine,______ (a) grooving

(c) cutting

(d) parting

is the process of cutting a workpiece into two parts.

(b) parting

(c) cutting

(d) (a) and (b)

Q. 65 The process of embossing a diamond shaped regular pattern on surface of workpiece is called as (a) embossing Q.66

Q.67

(b) knurling

(c) grooving

(d) pattern making

The knurling helps in a) improving the strength of material

b) providing a non-Blipgriponthesurface.

c) saving of material

d) both (b) and (c)

In drilling operation on lathe machine, a) workpiece as well as drill are rotating in same direction. b) workpiece as well as drill are rotating in opposite direction. c) workpiece is rotating while drill is not rotating. d) workpiece is stationary while drill is rotating.

Q.68

In drilling operation on lathe machine,_________

.

a) rotating drill is fed against stationary workpiece. b) non-rotating drill is fed against rotating workpiece. c) rotating drill is fed against rotating workpiece. d) rotating workpiece is fed against stationary drill. Q. 69 In lathe machine, during drilling operation, the drill bit is supported by (a) tool post

(b) spindle

(c) carriage

(d) none of the above

Q. 70 In lathe machine, the of enlarging the already existing hole in workpiece is carried by the operation known as (a) drilling

(b) enlarging

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(c) boring 203

(d) finishing

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Q. 71 In thread cutting operation on lathe machine, the following element has to engage with lead screw. (a) Tailstock

(b) Spindle

(c) Carriage

(d) Lathe bed

Q. 72 In thread cutting operation on lathe machine, there has to be engagement between (a) head stock and tailstock

(b) lead screw and tailstock.

(c) apron and cross-slide

(d) lead screw and split nut.

Q. 73 In thread cutting operation on lathe, these has to be a definite relation between a) rotary motion of workpiece and linear motion of tool. b) rotary motion of workpiece and rotary motion of tool. c) rotary motion of workpiece and linear motion of tailstock. d) rotary motion of workpiece and rotary motion of spindle. Q.74

In thread cutting operation on lathe. a) the motion of carriage is manual b) the motion of carriage is mechanized c) the motion of carriage is perpendicular to axis of workpiece d) both (band (c))

Q.80

______ operation can be carred out on centre lathe. a) Drilling

Q.81

c) shaping

d) None of the above

______ operation cannot be carried out on lathe machine. a) Shaping

Q.85

b) Milling

b) Drilling

c) Threading

d) Both (a)and (b)

The machine tool used for making the hole in the workpiece by forcing the non-rotating tool into rotating workpiece is called as______. (a) drilling machine

(b) boring machine

(c) lathe machine

(d) all (a), (b) and (c)

(c) Turret lathe

(d) All (a), (b) and (c)

(c) centre lathe

(d) none of the above

Q. 86 _________ is a type of lathe. (a) Speed lathe Q.87

(b) Bench lathe

Engine lathe is also known as________. (a) motor lathe

(b) turning lathe

Q. 88 Speed lathe is a_______

Q.89

(a) low production

(b) medium production

(c) high production

(d) special purpose

Term capsten is related to_______. (a) millingmachine

Q.99

lathe machine.

(b) drilling machine

Term turret is related to_______ (a) lathe machine

.

(b) millingmachine

VISION ENGINEERING ACADEMY, PUNE

(c) grinding machine (d) lathe machine

204

c) drilling machine

(d) grinding machine

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Q.91

In turret lathe, turret is present in place of _____. (a) headstock

Q.92

d) six

b) square

c) hexagon

d) triangle

b) speed lathe

c) turret lathe

d) Both (a) and (b)

b) Milling machine

c) Lathe machine

d) Universal machine

Which of the following machines is called as universal machine? a) Lathe machine

Q.99

c) four

The following machine is called as mother of all machine tools : a) Shaping machine

Q.97

b) three

______ is an example of low production lathe. a) Tool room lathe

Q.96

(d) cross-slide

The shapes of turret in turret lathe is ______. a) Rectangle

Q.95

(c) spindle

Turret can hold ____tools. a) two

Q.94

(b) tailstock

b) Grinding machine c) Milling machine

d) Shaping machine

The process of making cylindrical hole in the workpiece, using mult-point cut tool is calledas (a) boring

(b) drilling

(c) threading

(d) both (a) and (b)

Q.100 The machine tool used for making the hole in the workpiece by forcing the rote tool into stationary workpiece is called as______. (a) drilling machine

(b) lathe machine

(c) boring machine

(d) all (a), (b) and (c)

Q.101 In drilling machine, a) drill is stationary and workpiece is rotating. b) drill is rotating and workpiece is stationary. c) drill is rotating and workpiece is rotating. d) drill is moving and workpiece is moving. Q.102 In drilling machine, during operation the workpiece (a) is rotating

(b) is having linear as well as rotary motion

(c) is stationary

(d) is having linear motion.

Q. 104 The machine used for making the cylindrical hole in the workpiece is called as (a) milling machine.

(b) drilling machine.

(c) shaping machine.

(d) cylindrical grinding machine.

Q. 105 The drill is a (a) single point cutting tool

(b) two point cutting tool.

(c) line cutting tool.

(d) multipoint cutting tool.

Q. 106 In drilling machine during operation, the drill is given (a) only rotary motion

(b) only linear motion.

(c) both linear and rotary motion

(d) (b) or (c)

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Q. 107 In drilling machine the linear motion of drill is called a) speed

b) depth of cut

Q. 108 The end of drill bit is ________ (a) semi-circular

c) travel

d) feed

in shape.

(b) flat

(c) conical

d) (b) or (c)

Q. 109 In drilling machine, the drill has (a) one type of motion

(b) two types of motions,

(c) three types of motions

(d) four types of motions.

Q.110 In drilling machine, the drilling head is supported by (a) work table Q.111 _______

(b) column

(c) base

(d) chuck.

is not a part of drilling machine.

(a) Column

(b) Carriage

(c) Spindle

(d) Worktable

(c) Spindle

(d) none of the above

(c) base

(d) worktable

Q.112 ______ is a part of drilling machine. (a) Turret

(b) Compound rest

Q. 113 In drilling machine, the chuck is mounted on (a) spindle

(b) column

Q.114 In drilling machine, worktable is mounted on________. (a) column

(b) drilling head

(c) chuck

(d) none of the above

Q.115 The basic element of drilling machine is______. (a) base

(b) column

(c) worktable

(d) all (a), (b) and (c)

Q.116 In drilling machine, ________supports entire structure of machine. (a) base

(b) column

(c) head

(d) table

Q.117 ______ of drilling machine is used for supporting drilling head and worktable. (a) Base

(b) Table

(c) Column

Q.118 The work table of drilling machine has ______

(d) Structure

type of motion.

(a) Vertical

(b) horizontal

(c) vertical and circular

(d) none of the above

Q. 119 In drilling machine, the workpiece is mounted on (a) spindle

(b) bed

(c) column

(d) work table

Q. 120 In drilling machine, the work table has a) rotary motion about base

b) up and down motion along the column.

c) swing about the axis of the column d) both (b) and (c) Q.121 In drilling machine, the top surface of worktable is_____

.

(a) plane and flat

(b) having circular grooves

(c) having T-slots

(d) having I section

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Q. 123 The drilling head contains (a) work table

(b) drive mechanism

c) feed mechanism

(d) both (b) and (c)

Q. 124 The drive mechanism of drilling machine consists of (a) clutch

(b) belt drive

(c) gear box

(d) (b) or (c)

Q.125 In drilling machine, drive mechanism and feed mechanism are placed in _____ (a) gearbox

(b) column

(c) drilling bead

(d) base

Q.126 In drilling machine, the feeding of spindle is____. (a) power feed

(b) manual feed

(c) gravity feed

(d) (a) or (b)

Q. 127 _______ is the upper most part of the drilling machine. (a) Drilling head

(b) Work table

(c) Spindle

(d) Chuck

Q. 128 The following operation cannot be performed on drilling machine (a) Tapping

(b) Trepanning

(c) Grooving

(d) Boring

Q. 129 Which of the following operations is performed before reaming ? (a) Boring

(b) Drilling

(c) Grooving

(d) Tapping

(c) circular

(d) chamfered

(c) tapping

(d) parting

Q. 131 The end of drilled hole is (a) flat

(b) conical

Q. 132 The following is a finishing operation (a) drilling

(b) reaming

Q. 133 The existing hole can be enlarged to a required size by (a) drilling

(b) reaming

(c) boring

(d) both (b) and (c)

(c) flat

(d) (b) or (c)

c) flat

d) chamfered

Q. 134 The end of reaming tool is (a) Semi-circular

(b) conical

Q.135 The end of the bored hole is a) conical

b) circular

Q.138 The recess for bolt heads or nut can be provided by a) drilling

b) boring

c) counter-boring

d) counter-sinking

c) Reaming

d) boring

Q.140 The depth of enlarged hole is small in a) Counter-boring

b) spot-facing

Q.141 The process of chamfering the entrance of a drilled hole is called as a) Chamfering

b) counter-facing

c) Counter-sinking

d) spot-sinking

Q.142 The counter-sinking operation can be performed on (a) grinding machine (b) shaping machine

(c) drilling machine

(d) Both (b) and (c).

Q. 143 The recess for flat-head screw can be provided by (a) spot-facing

(b) counter-facing

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(c) counter-sinking

(d) chamfering

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Q.144 The drilling operation can be performed on (a) milling machine

(b) drilling machine

(c) lathe machine

(d) both (b) and (c)

Q. 145 The counter-sinking operation has to be proceeded by (a) threading

(b) drilling

(c) spot-facing

(d) counter-boring

Q. 146 The tool used for making internal threads is called as (a) lead screw

(b) screw tool

(c) tap

(d) drill

Q.148 The following process can be used for making the large size holes (a) drilling

(b) trepanning

(c) counter-sinking

(d) reaming.

Q.149 The following operation cannot be carried out on drilling machine. (a) Internal threading (b) External threading (c) Boring

(d) Both (a) and (b)

Q. 155 In bench drilling machine, the spindle is driven by electric motor through.______. (a) gear box

(b) clutch

(c) cone pulley drive (d) (a) or (c)

Q.156 Bench drilling machine is also known as_______. (a) piller drilling machine

(b) radial drilling machine

(c) portable drilling machine

(d) sensitive drilling machine

Q.158 Piller drilling machine is also known as_______. (a) bench drilling machine

(b) sensitive drilling machine

(c) upright drilling machine

(d) radial drilling machine

Q. 159 In_____

drilling machine, the motion of worktable is controller by lead screw.

(a) bench

(b) piller

(c) radial

(d) all (a), (b) or (c)

Q. 160 In_________ drilling machine, the work table is not stationary. (a) bench

(b) piller

(c) upright

(d) all (a), (b) and (c)

(c) by gravity

(d) (a) or (b)

Q. 161 In pillerdrilling machine, the feed is____. (a) manual

(b) automatic

Q. 162 _____ drilling machine is the largest andmost versatile of all machines. (a) Filler

(b) Bench

(c) Upright

(d) Radial

Q.163 The arm can swing around column through an arc of 180°. If must be ____ frilling machine. (a) radial Q. 164 In __________ (a) radial

(b) piller

(c) bench

(d) (a)or(b)

drilling machine, the work table is stationary. (b) bench

(c) piller

(d) all (a), (b) or (c)

Q.166 The radial arm is present on a) portable drilling machine

b) bench drilling machine

c) piller drilling machine

d) none of the above

Q.167 In drilling machine______ is a hollow part in which drill is inserted. a) column

b) chunk

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c) drilling head 208

d) none of the above © VISION ENGINEERING Publications

Q.168 In drilling machine, the spindle of drilling machine can _______. (a) only rotate

(b) moves up and down

(c) rotate as well as move up and down

(d) only reciprocate

Q.169 In _____drilling machine, the holes can be drilled in different locationswithout moving workpiece. (a) radial

(b) bench

(c) piller

(d) all (a), (b) and (c)

c) upright

(d) none of the above

Q.170 Electrician uses____ drilling machine. a) bench

b) piller

Q.171 In radial drilling machine, the up and down motion of radial arm is achieved ___. a) manually

b) due to gravity

c) with the help of cone pulley drive

d) with the help of lead screw motor

Q.172 The grinding process gives a) good surface finish with substantial material removal. b) good surface finish with negligible material removal. c) good surface finish without material removal. (d) none of the above Q. 173 _______ is the process of imparting the good surface finish with the negligible removal of the material. (a) Drilling

(b) Turning

(c) Grinding

(d) Both (b) and (c)

c) high speed steel

d) tool steel

Q.174 Grinding wheels are made of _____. a) abrasive particles b) smooth particles Q.175 The grinding wheel can be made of a) Tool steel

b) plain carbon steel c) silicon carbide

d) high speed steel

Q.176 The purpose of grinding operation is _____. a) to provide good surface finish and high dimensional accuracy b) material removal c) to give required shape to workpiece d) all (a) (b) and (c) Q.179 ______ is not a type of grinding machine. a) Cylindrical grinding machine

b) Vertical grinding machine

c) Centreless grinding machine

d) Surface grinding machine

Q.180 _______ grinding machine is a type of grinding machine. (a) Vertical

(b) Horizontal

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(c) Face

209

(d) Centreless

© VISION ENGINEERING Publications

Q.181 In cylindrical grinding machine a) the grinding wheel and workpiece rotate in opposite direction. b) the grinding wheel and workpiece rotate in same direction. c) the grinding wheel is rotating and workpiece in stationary. d) the grinding wheel and workpiece are stationary. Q.183 In internal grinding, the required grinding speed is 25 m/s. If the spindle speed is 30000 r.p.m., the diameter of grinding wheel is_____. (a) 16 mm

(b) 8 mm

(c) 50 mm

(d) 16 m.

Q. 184 In cylindrical grinding machine, the grinding wheel has a) rotary motion. b) rotary and longitudinal motion. c) rotary motion, longitudinal motion and cross feed. d) rotary motion and cross feed. Q. 185 In cylindrical grinding machine, the workpiece has a) rotary motion. b) rotary and longitudinal motion. c) rotary motion, longitudinal motion and cross feed. d) rotary motion and cross feed. Q. 186 In cylindrical grinding machine, the grinding wheel has (a) one type of motion.

(b) two types of motions.

(c) three types of motions.

(d) four types of motions.

Q. 187 The cylindrical grinding machine is used for the grinding of _____. (a) crank pins and piston pins

(b) rollers of bearings

(c) inner surfaces of ball bearing rings

(d) shafts and axles

Q. 188 In following machine, the material removal is minimum. (a) Lathe

(b) Drilling

(c) Internal grinding

(d) Tool and cutter grinding

Q. 190 The grinding of rollers of bearings and piston pins can be carried out on. a) cylindrical grinding machine

b) centreless grinding machine

c) surface grinding machine

d) special purpose grinding machine

Q.191 In centreless grinding machine a) there are two grinding wheels b) there is one grinding wheel and one regulating wheel. c) only one grinding wheel. d) there is one grinding wheel and two regulating wheels. VISION ENGINEERING ACADEMY, PUNE

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Q.192 In centreless grinding, the workpiece has a) one type of motion

b) two types of motions.

c) three types of motions

d) no motion.

Q. 193 In centreless grinding, the axial motion to the workpiece is provided by a) electric motor

b) grinding wheel

c) regulating wheel

d) lead screw

Q. 194 In centreless grinding, a) the grinding wheel and regulating wheel rotate in opposite direction. b) the grinding wheel and -regulating wheel rotate in same direction. c) the grinding wheel rotates and regulating wheel in stationary. d) none of the above. Q. 195 The internal grinding machine is used for the grinding of

_______.

a) crank pins and piston pins

b) inner surfaces of ball bearing rings

c) shafts and axles

d) all of the above

Q. 196 The centreless grinding machine is used for the grinding of a) inner surfaces of ball bearing rings

b) gear tooth profile.

c) bores of cylinders.

d) none of the above.

Q.199 In horizontal spindle surface grinding machine, the grinding wheel is ____. a) Solid circular

b) Hollow circular

c) Segmental

d) None of the above

Q. 201 In horizontal spindle surface grinding machine, the work table is_______ (a) circular

(b) rectangular

(c) segmental

.

(d) none of the above

Q. 202 In horizontal spindle surface grinding machine, the work table has ______motion. (a) redprocatory

(b) rotary

(c) no

(d) both (a) and (b)

Q. 203 In vertical spindle surface grinding machine, the work table has ____ motion, (a) redprocatory

(b) rotary

(c) no

(d) both (a) and (b)

Q. 204 In vertical spindle surface grinding machine, the depth of cut is provided by _____. a) vertical feed of work table b) vertical feed of grinding wheel c) vertical feed of work table as well as grinding wheel d) horizontal feed of grinding wheel Q. 205 In vertical spindle surface grinding machine, the grinding wheel is ______. (a) solid circular

(b) segmental

(c) hollow circular

(d) (a) or (c)

Q. 206 In vertical spindle surface grinding machine, the work table is______. (a) circular

(b) rectangular

(c) segmental

(d) (a) or (b)

Q. 207 In surface grinding, the workpiece is mounted on _____ work table. (a) hydraulic

(b) pneumatic

VISION ENGINEERING ACADEMY, PUNE

(c) magnetic 211

(d) (b) or (c)

© VISION ENGINEERING Publications

Q. 208 In vertical spindle surface grinding machine the work table is______ (a) vertical

(b) horizontal

(c) inclined

(d) (a) or (b)

Q. 209 Tool and cutter grinder is a type of ________. (a) cylindrical grinding machine

(b) surface grinding machine

(c) centreless grinding machine

(d) none of the above

Q. 210 Cam grinding machine is an example of (a) cylindrical

_____grinding machine.

(b) centreless

(c) tool and cutter

(d) none of the above

(c) grinding

(d) all (a), (b) and (c)

Q.211 ______ is a chipless operation. (a) drilling

(b) turning

Q. 212 In following machine the workpiece is stationary. (a) Lathe

(b) Drilling

(c) Grinding

(d) Both (a) and (c)

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CHAPTER 7 ====================================================================================================================

Answer Key ============================================================================================================= Q.1

(c)

Q.2

(a)

Q.3

(b)

Q.4

(c)

Q.5

(c)

Q.6

(a)

Q.7

(b)

Q.8

(d)

Q.9

(b)

Q.10 (c)

Q.11 (d)

Q.12 (c)

Q.13 (d)

Q.14 (b)

Q.15 (a)

Q.16 ()

Q.17 ()

Q.18 (b)

Q.19 (b)

Q.20 (a)

Q.21 (c)

Q.22 (d)

Q.23 (d)

Q.24 (c)

Q.25 (d)

Q.26 (b)

Q.27 (a)

Q.28 (d)

Q.29 (c)

Q.30 (c)

Q.31 (d)

Q.32 (c)

Q.33 (d)

Q.34 (c)

Q.35 (b)

Q.36 (d)

Q.37 (b)

Q.38 (b)

Q.39 (c)

Q.40 (b)

Q.41 (a)

Q.42 (a)

Q.43 (d)

Q.44 (c)

Q.45 ()

Q.46 (b)

Q.47 (d)

Q.48 (b)

Q.49 (a)

Q.50 (c)

Q.51 (c)

Q.52 (d)

Q.53 (a)

Q.54 ()

Q.55 (b)

Q.56 (c)

Q.57 (c)

Q.58 (d)

Q.59 (c)

Q.60 (d)

Q.61 (c)

Q.62 (d)

Q.63 (d)

Q64. (b)

Q.65 (b)

Q.66 (b)

Q.67 (c)

Q.68 (b)

Q.69 (d)

Q.70 (c)

Q.71 (c)

Q.72 (d)

Q.73 (a)

Q.74 (b)

Q.75 ()

Q.76 ()

Q.77 ()

Q.78 ()

Q.79 ()

Q.80 (a)

Q.81 (a)

Q.82 ()

Q.83 ()

Q.84 ()

Q.85 (c)

Q.86 (d)

Q.87 (c)

Q.88 (a)

Q.89 (d)

Q.99 (a)

Q.91 (b)

Q.92 (d)

Q.93 ()

Q.94 (c)

Q.95 (d)

Q.96 (c)

Q.97 (a)

Q.98 ()

Q.99 (b)

Q.100 (a)

Q.101 (b)

Q.102 (c)

Q.103 ()

Q.104 (b)

Q.105 (d)

Q.106 (c)

Q.107 (d)

Q.108 (c)

Q.109 (b)

Q.110 (b)

Q.111 (b)

Q.112 (c)

Q.113 (a)

Q.114 (a)

Q.115 (d)

Q.116 (a)

Q.117 (c)

Q.118 (c)

Q.119 (d)

Q.120 (d)

Q.121 (c)

Q.122 ()

Q.123 (d)

Q.124 (d)

Q.125 (c)

Q.126 (d)

Q.127 (a)

Q.128 (c)

Q.129 (*)

Q.130 ()

Q.131 (b)

Q.132 (b)

Q.133 (c)

Q.134 (*)

Q.135 (c)

Q.136 ()

Q.137 ()

Q.138 (c)

Q.139 ()

Q.140 (b)

Q.141 (c)

Q.142 (e)

Q.143 (c)

Q.144 (d)

Q.145 (b)

Q.146 (c)

Q.147 ()

Q.148 (b)

Q.149 (b)

Q.150 ()

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© VISION ENGINEERING Publications

Q.151 ()

Q.152 ()

Q.153 ()

Q.154 ()

Q.155 (c)

Q.156 (d)

Q.157 ()

Q.158 (c)

Q.159 (b)

Q.160 (d)

Q.161 (b)

Q.162 (d)

Q.163 (a)

Q.164 (a)

Q.165 ()

Q.166 (d)

Q.167 (b)

Q.168 (c)

Q.169 (a)

Q.170 (d)

Q.171 (d)

Q.172 (b)

Q.173 (c)

Q.174 (a)

Q.175 (c)

Q.176 (a)

Q.177 ()

Q.178 ()

Q.179 (b)

Q.180 (d)

Q.181 (b)

Q.182 ()

Q.183 (a)

Q.184 (c)

Q.185 (a)

Q.186 (c)

Q.187 (d)

Q.188 (c)

Q.189 ()

Q.190 (b)

Q.191 (b)

Q.192 (b)

Q.193 (c)

Q.194 (b)

Q.195 (b)

Q.196 (d)

Q.197 ()

Q.198 ()

Q.199 (a)

Q.200 ()

Q.201 (b)

Q.202 (a)

Q.203 (b)

Q.204 (b)

Q.205 (b)

Q.206 (a)

Q.207 (c)

Q.208 (b)

Q.209 (d)

Q.210 (d)

Q.211 (c)

Q.212 (b)

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VISION ENGINEERING ACADEMY, PUNE

214

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