Ce Phy Mock Paper D2

Kwok Tak Seng Catholic Secondary School S.5 Mock Examination 2004-05

PHYSICS PAPER II 7 - 3 -2005 Time allowed : 1 hour

This paper must be answered in English

Total no. of pages : 14

1.

Read carefully the instructions on the Answer Sheet and insert the information required in the spaces provided.

2.

When told to open this paper, check that all the questions are there. Look for the words “END OF PAPER” after the last question.

3.

All questions carry equal marks.

4.

ANSWER ALL QUESTIONS. You should mark all your answers on the Answer Sheet.

5.

You shourld mark only ONE answer to each question. If you mark more than one answer, you will receive NO MARKS for that question.

5.

No marks will be deducted for wrong answers.

6.

There is a list of physics formulae which you may find useful.

Useful Formulae in Physics (a)

Relationships between initial velocity u, uniform acceleration a, final velocity v and displacement travelled s after time t : v = u + at 2 s = ut + 21 at 2

2

v = u + 2 as (b)

Potential energy gained by a body of mass m when raised through a height h is mgh.

(c)

Kinetic energy of a body of mass m moving with speed v 2 is 21 mv

(d)

Power = force × velocity

(e)

Equivalent resistance of two resistors R1 and R2 : (i) in series = R1 + R2 (ii) in parallel =

(f)

R1 R2 R1 + R2

Power = potential difference × current

S5/PHY-II/ P.2

There are 45 questions. If necessary, take g = 10 m s-2. Unless otherwise specified, all the cells are assumed to have negligible internal resistance. 1.

2.

Consider three heat sinks made of the following materials. If their designs are the same, which one has the best performance? Material Specific heat capacity Density -1 -1 Aluminium 2700 kg m-3 900 J kg °C Glass 2400 kg m-3 600 J kg-1 °C-1 Copper 8900 kg m-3 370 J kg-1 °C-1 A Aluminium, because it has the highest specific heat capacity. B Copper, because it has the lowest specific heat capacity. C Glass, because the heat sink is the lightest. D Copper, because the heat sink has the highest heat capacity. The following figure shows the structure of a thermos flask.

plastic stopper

vacuum flask (the vacuum is between the double glass walls) silvery glass wall insulated support

3.

Which of the components of the thermos flask is best at: preventing heat loss by preventing heat loss by preventing heat loss by conduction convection radiation A vacuum between the silvery glass walls plastic stopper double glass walls B vacuum between the plastic stopper insulated support double glass walls C plastic stopper insulated support silvery glass walls D insulated support vacuum between the silvery glass walls double glass walls Which of the following descriptions about evaporation of water is/are correct? (1) The average kinetic energy of water decreases during evaporation. (2) Evaporation takes place only when the water temperature is greater than the room temperature. (3) Water absorbs energy when it boils as well as it evaporates. A (1) and (2) only B (1) and (3) only C (2) and (3) only D (1), (2) and (3)

S5/PHY-II/ P.3

4.

5.

The diagram below shows the apparatus used for finding the specific latent heat of vaporization of water.

Which of the following factors will cause the result obtained to be smaller than the true value? (1) Some energy supplied by the heater is lost to the surroundings. (2) Some water splashes out of the cup as it boils. (3) Some steam condenses and drips back into the polystyrene cup. A (1) only B (2) only C (1) and (2) only D (2) and (3) only In an experiment, a trolley with a card of width 5 cm passes through the light gate in 0.25 s. What is the following quantity? 5 cm = 20 cm s−1

0.25 s

6.

A Instantaneous speed of the trolley passing the light gate. B Average speed of the trolley passing the light gate. C Instantaneous acceleration of the trolley passing the light gate. D Average acceleration of the trolley passing the light gate. The following graph shows that quantity X is directly proportional to time t. X

t/s Which of the following can be the quantity X? (1) Velocity of a freely falling object with negligible air resistance. (2) Displacement of an object moving at constant velocity. (3) Distance travelled by an object moving with constant acceleration. A (1) and (2) only. B (1) and (3) only. C (2) and (3) only. D (1), (2) and (3).

S5/PHY-II/ P.4

7.

The following velocity-time graph records the motion of a trolley moving on a runway.

Which of the following statements about the motion of the trolley is/are true? (1) The trolley changes travelling direction at t = 2.6 s. (2) The speed of the trolley before t = 2.6 s is almost twice that after t = 2.6 s. (3) The displacement of the trolley is zero. A (2) only. B (1) and (2) only. C (1) and (3) only. D (1), (2) and (3). (Refer to the last question.) In the following figure, Tommy stands at a cliff and throws a stone vertically upwards at 15 m s−1. The stone rises to the highest point and then falls into the sea.

8.

Which of the following graphs best represents the variation of the velocity v of the stone with time t after it leaves the hand of Tommy and before it reaches the sea? (Take upwards as positive.) A B v

v

t

C

t

D

v

t

v

t

S5/PHY-II/ P.5

9.

10.

Which of the following is/are the direct implication(s) of Newton's first law? (1) A boy standing on a bus is 'pulled' backwards when the bus starts moving. (2) On a smooth surface, when you push another person in front of you, you will move backwards. (3) The balls of different masses reach the ground at the same time in Galileo's experiment (carried out on the tower of Pisa). A (1) only B (2) only C (3) only D (1) and (2) only Which of the following graphs show(s) that a constant resultant force is acting on the object? (1) (2) s v

t

(3)

t

a

t

11.

A (1) and (2) only B (1) and (3) only C (2) and (3) only D (1), (2) and (3) In the figure below, a block of mass x kg is suspended by a string and a horizontal force.

θ

T

F x kg

If the tension in the string is T, which of the following statements is INCORRECT? A T sin θ = F B In order to keep the block stationary, when θ increases, F should increase. C T cos θ = x D F = 10x × tan θ

S5/PHY-II/ P.6

12.

Mary of weight W stands inside a lift. The life is moving upwards at a constant acceleration. Let the normal force exerted on Mary by the floor be R, which of the following statements is/are correct? (1) R is greater than W in magnitude. (2) R and W are in opposite directions. (3) R and W form an action-and-reaction pair according to Newton's third law. A (1) only B (2) only C (1) and (2) only D (2) and (3) only

13.

A ball is pushed up an inclined plane by a force of 10 N to a height of 5 m from the ground.

10 N

1 kg

5m

30°

Which of the following statements is/are correct? (1) Work done by the force is 50 J. (2) The potential energy gained by the ball is 50 J. (3) If the force makes an angle with the surface of the inclined plane, the work done by the force would be greater. A (2) only. B (1) and (2) only. C (1) and (3) only. D (1), (2) and (3). 14.

CN Tower in Canada is 533 m tall and it is the tallest building in the World. If a stone of 200 g is thrown vertically upwards at 5 m s−1 at the top of the CN Tower, what is the kinetic energy of the stone when it drops to the ground? Neglect air resistance. A 2.5 J B 535 J C 1070 J D 2140 J

15.

A ball falls from a height of h to the ground and bounces back to the same height. Which of the following statements is/are correct? (1) The momentum of the ball just before collision and that just after collision are the same. (2) The speed of the ball just before collision and that just after collision are the same. (3) The net force acting on the ball during the downward journey and that during the upward journey are same. A (1) and (2) only B (1) and (3) only C (2) and (3) only D (1), (2) and (3)

S5/PHY-II/ P.7

16.

A string of waves is coming to particle A from the left. travelling direction

A •

How will particle A move? A

B •A

A•

moves along the wave C

D

•A

A•

moves along a vertical line 17.

moves along the wave

moves along a vertical line

In the following figure, two loudspeakers X and Y are connected to a signal generator, and a microphone is connected to a CRO.

When the microphone moves from P to Q, where P lies on the centre line between X and Y, the reading of the CRO varies as shown in the following figure. Which of the following figures best shows the display of CRO when the frequency is doubled?

S5/PHY-II/ P.8

18.

You can see the signature on the passbook because of the ray X. What is X? X passbook

19.

20.

21.

A Infra-red B Visible light C Ultra-violet D X-ray In the following figure, a girl 150 cm tall stands facing a 75 cm long mirror, the bottom edge of which is 30 cm above the floor.

If the girl's eyes are 10 cm below the top of her head, which of the following statements is WRONG? A The girl cannot see her whole image no matter how far she is from the mirror. B The girl cannot see her whole image no matter how high she hangs the mirror. C The distance between the girl and the mirror is the same as the distance between the girl's image and the mirror. D The girl's image can be photographed. What is/are the advantage(s) of right-angled prisms over plane mirrors in periscopes? (1) The image is erect. (2) Multiple images are not formed. (3) The image is of the same size as the object. A (2) only B (1) and (2) only C (2) and (3) only D (1), (2) and (3) A light ray travels from medium I to medium IV, as shown in the following figure. Arrange the refractive indices of the media in ascending order. A B C D

IV < II < I < III III < IV < II < I IV < II < III < I III < I < IV < II

S5/PHY-II/ P.9

22.

In the following diagram, intervals AB, BC, CD, DE and EF are of equal length. An object is placed at O. When a lens is put in front of the object, an image of the object is formed at I. O A

B

I C

D

E

F

Which of the following show(s) the possible position(s), type(s) and focal length(s) of the lens?

23.

24.

Position

Type

Focal length

(1)

C

convex lens

about 1 interval

(2)

F

concave lens

about 2 intervals

(3)

A

convex lens about 2 intervals A (1) only B (3) only C (1) and (2) only D (2) and (3) only Some letters are viewed by a lens. The image of the letters is shown in the following figure.

If the lens is moved away from the letters, which of the following correctly describes how the appearance of the image changes? A magnified, erect → magnified, inverted → diminished, inverted B magnified, erect → magnified, inverted → more magnified, inverted C magnified, erect → diminished, inverted → more diminished, inverted D magnified, erect → magnified, inverted → more magnified, erect The following figures show the waveform of the four different musical notes. (1) (2)

(3)

(4)

Which pair of the notes have the same loudness? A (1) and (3) B (2) and (3) C (2) and (4) D (1) and (4)

S5/PHY-II/ P.10

25.

26.

The following figure shows electric field lines coming from three point charges X, Y and Z.

What are the charges of X, Y and Z? X Y A. negative negative B. negative positive C. positive negative D. positive negative What would happen when key K is closed?

Z negative positive negative positive

K V A M

N

(1) (2) (3)

27.

The voltmeter reading increases. The ammeter reading increases. Bulb N becomes brighter. A (1) and (2) only B (1) and (3) only C (2) and (3) only D (1), (2) and (3) A lamp is switched on and it draws a current of I amperes for t minutes. How much charge has passed through the lamp? A It C B 60It C C D

28.

I C 60t t C I

In the following circuit, the resistance of R2 is half of that of R1. When S1 is closed, the ammeter reads 1.6 A. What is the reading of the ammeter when both S1 and S2 are closed? A 0. 6 A 3V B 2.8 A C 3.6 A D 4.2 A A 5Ω

R1

S1

R2

S2

S5/PHY-II/ P.11

29.

In the following figure, all lamps are identical. What is the ratio of the power of X to that of Y? A 1:1 B 3:1 C 1:7 D 9:1

X •

Y

•

30.

• •

In the following figure, the electric iron is not properly connected.

Which of the following arrangements is/are required? (1) The fuse should be connected to wire Z instead of wire X. (2) The switch S should be connected to wire X instead of wire Z. (3) The wire Y should not be connected to the metal case. A (1) only B (2) only C (1) and (3) only D (2) and (3) only

The following figure shows a current flowing along a wire, from X to Y.

31.

X

Y

Which of the following figures best represents the magnetic field produced? A B X

Y

C

Y

D X

32.

X

Y

X

The following figure shows an electric bell. Which of the following methods can increase the loudness of the hitting sound? (1) Push the bell-push faster and harder. (2) Use a larger soft-iron core. bell-push (3) Connect more cells in series with the battery. A (3) only B (1) and (2) only C (1) and (3) only soft-iron core D (2) and (3) only

Y

S5/PHY-II/ P.12

33.

In the following figure, a magnet is moving towards a coil at uniform speed.

Y •

S N

X •

− +

to voltmeter

Which of the following graphs best represents the reading of the voltmeter when the magnet moves from X to Y? A B

C

34.

D

In the following figure, a simple magnetic tape playback system is reading the magnetic pattern on a tape. At which of the following positions is the magnitude of the galvanometer reading greatest?

A B C D

P Q R S

S

R

Q

movement of the tape P

S5/PHY-II/ P.13

35.

36.

In the following figure, a simple generator rotates clockwise to the observer.

Which of the following statements about the generator is/are correct? (1) It is an a.c. generator. (2) The current produced passes through the lamp from X to Y. (3) The brightness of the lamp increases with the rotation speed of the coil. A (1) only B (3) only C (1) and (2) only D (2) and (3) only The figure below shows two different power transmission systems, X and Y.

system X heater

system Y heater

37.

If the total resistance of the transmission cables in both systems are 10 Ω, what is the ratio of the power loss in transmitting power in system X to that in system Y? Assume no power loss in transformers. A 10 : 1 B 15 : 1 C 20 : 1 D 25 : 1 In the following figure, the readings of a GM counter are significant only at X and Y.

Which of the following methods can significantly reduce the reading of the GM counter at X? (1) Cover the source with 5 mm of aluminum. (2) Apply a magnetic field pointing into the paper. (3) Reverse the electric potential across the plates. A (2) only B (3) only C (1) and (2) only D (1), (2) and (3)

S5/PHY-II/ P.14

38.

39.

40.

41.

Radiation workers are required to wear a film badge. What is the function of the film badge? A Monitoring the radiation the workers expose to B Showing people that they are radiation workers C Shielding workers from radiation D Warning people of high radioactive regions 232 228 A nucleus 90 X is decayed to 89Y . What is/are probably emitted in the process? A One α particle and one β particle B One α particle and γ ray C Four α particles D Four β particles The half-life of a radioactive source is 3 days. If the initial mass of the source is 100 g, what is the weight of the decayed nuclei after 12 days? A 6.25 g B 25 g C 75 g D 93.75 g Which of the following is NOT correct to both nuclear reactor and atomic bomb? A Nuclear fission occurs inside them. B The mass of the nuclear materials inside them is larger than the critical mass. C Huge amount of heat is given out inside them. D The rate of nuclear reaction inside them is the same.

Directions : Each question below (Questions 42-45) consists of two statements. Decide whether each of the two statements is true or false. If both are true, then decide whether or not the second statement is a correct explanation of the first statement. Then select one option A - E according to the following table : A.

1st statement True

B.

True

C. D.

True False

2nd statement True 2nd statement is a correct explanation of the 1st statement True 2nd statement is a NOT correct explanation of the 1st statement False --True ---

1st statement

2nd statement

42.

The displacement of a freely falling object increases with time.

The acceleration of a freely falling object increases with time.

43.

The velocity of an object is directly proportional to the resultant force acting on the object.

An object in uniform motion must have zero resultant force.

44.

The brightness of a bulb depends only on the voltage across it.

The larger the voltage across the bulb, the more the energy is given to the bulb by each coulomb of charge.

45.

In an a.c. generator, increasing the rotating speed of the coil can increase the amplitude of the induced voltage.

The voltage induced in a conductor increases with the speed at which the conductor cuts through the magnetic field lines.

END OF PAPER