Part B 2006

Marks Queatiron16 (6 marks) A projectileleavesthe groundat point A with velocity compongntsas showniq _th,e diagram.It follows the path givgnby the dottedline andlandsat point B. uy= 40 mls

(a)

Statethe horizontal componentof the projectile's velocity when it lands.

(b)

Find the magnitude of the initial velocity of the projectile.

(c)

Calculate the maximum height attainedby the projectile.

(d)

Calculate the range of the projectile, if it lands level with its starting position.

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Quostion17 (6 marks) F'artsof 4 spacemissioninv{lve a spacecraftspendingtime in geostationary orbit, and then returning safelyto Earth. Analysethe forcesactingon this spacecraftduringthesepartsof thEmission.

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EXAMIl{ATIOl{ 2006 HIGHERSCHOOTCERTIFICATE

Physics

CentreNumber

SectionI - Part B (continued) Student Number

Marks Question 18 (3 marks) An object is stationaryin spaceand located at a distance 10 000 km from the centre of a certain planet. It is found that 1.0 MJ of work needsto be done to move the object to a stationary point 20 000 km from the centre of the planet.

Calculatehow much more work needsto be done to move the object to a stationary point 80 000 km from the centreof the planet.

I I I

I

I

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435a

---------^ -^ -^ -^ -^

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3

Question19 (3 marks) The diagramshowsthe structureof a typical galvanometer. Scale

rr)

rr

Cnrrent-c.anying coil

/

\

Soft iron,core

Describe how the galvanometeroperatesas an application of the motor effect.

- 18@ Board of Studies NSW 2006

3

Marks Question 20 (8 marks) A balance was used to investigate the relationship between current and force. The balancewas set up with one copper rod fixed to it and a secondrod fixed above it, as shown in the diagram. Each rod was connectedto a sourceof current. The diagram is not to scale.

Copperrod Copperrod Electronic balance

.6m The copper rods were rigid, each was 2.6 m long, and they were parallel. The current in the upper rod was kept constantat 50 A. Different currentswere passedthrough the lower rod and the balance readins recorded for each current. The readinss are siven in the table below. Current in lower rod (A)

(a)

Balance reading

(ke)

2 .8

0.5485

8 .0

0.5480

12.2

0.5474

16.8

0.5470

20.0

0.5465

Identify the relative directions of the cuffents in both rods, and justify your answer.

Question20 continueson page2l

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Marks Question 20 (continued) (b)

Plot the data from the table onto the graph, using the scales and axes as indicated, and add the line of best fit (trend line).

)

0.5495 0.5490 bo

0.5485

bo

-

0.5480

d

c) t-r C)

()

0.5475

r-

0.5410 0.5465 0.5460 6

8

10121416

18

24

Currentin lower rod (A) (c)

Find the mass of the copper rod on the balance.

(d)

Calculate the distancebetween the two copper rods.

End of Question20

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Marks Question 21 (6 marks) Assess the impact on society and the environment of the potential applications of superconductors.

-22 O Board of StudiesNSW 2006

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2006 HIGHERSCHOOLCERTIFICATE EXAMIl{ATIOl{

Physics

CentreNumber

SectionI - Part B (continued) Student Number

Marks Question 22 (5 marks) A student drops a bar magnet onto a Iarge block of copper resting on the floor. The magnet falls towards the copper,slowing down as it comes close, then landing gently. (a)

Explain the physics responsiblefor this observation.

3

(b)

Predict what will happen if the experiment is repeated with a copper block cooled to approximately -50oC. Justify your prediction.

2

I 436a

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Marks Question 23 (6 marks) (a)

Draw labelled diagrams of the band structuresof an insulator, a semiconductor, and a conductor.

2

(b)

With referenceto your diagrams,describethe differencesin electrical resistance betweeninsulators.semiconductorsand conductors.

2

(c)

Explain how the addition of trace amounts of certain elements, such as phosphorus,can change the electrical resistanceof semiconductorsat a given temperature.

2

- 24@ Board of StudiesNSW 2006

2006 HIGHERSCHOOLCERTIFICATE EXAMINATION

Physics

CentreNumber

SectionI - Part B (continued) StudentNumber

Marks Question24 (3 marks) Discussthe origins of unwantedheatproductionin transformersand waysin which thesecanbe overcome.

r' ^

Pleaseturn over

I 436b

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3

Marks

Question25 (6 marks) A simplifiedcathoderay oscilloscope is depictedbelow. Electron gun Cathode Anode

Horizontal deflection plates

Path of electrons Bright spotwhere electronshit

Heater --*

Fluorescentscreen Vertical deflection plates (a)

Outline the roles of the deflection plates and the electrodesin the electron gun.

(b)

In a special investigation,the voltage between the cathode and the anode is increasedso that an electrongains a velocity of 0.60 c, where c is the speedof light. The electron startsfrom rest at the cathode. Calculate the mass of this electron in the laboratorv frame of reference.

(c)

The distancebetween the anode and the screen,as measuredin the electron's frame of reference,is 0.24 m. Calculate this distanceas measuredin the laboratory frame of reference.

_26 _ @ Board of StudiesNSW 2006

2006 HIGHERSCHOOLCERTIFICATE EXAMII{ATIOI{

Physics

CentreNumber

Section I - Part B (continued) StudentNumber

Marks Question 26 (4 marks) Beginning in the late 19th century, observations and experiments on black body radiation and the photoelectric effect led physicists to revise their existing model of light. Use the above as an example to explain how scientiststest and validate models.

I 437

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Marks Question 27 (4 marks) J. Plticker was the first to observecathoderays within gas dischargetubes.He inferred that the rays were a form of electromagneticradiation. (a)

Describe ONE subsequentobservation that led other scientists to argue that cathoderays were chargedparticles.

(b)

Identify ONE potential hazard associated with performing discharge tube investigations,and outline ONE safe work practice which addressesthis hazard.

_ 2 8_ @ Board of StudiesNSW 2006

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