Part A 2006

Given that G is the universal gravitational constant, and g is the magnitude of the accelerationdue to gravity, which statementis true? (A)

The valuesof G and g dependon location.

(B)

The values of G and g are independentof location.

(C)

G is the sameeverywherein the universe,but g is not.

(D)

g is the sameeverywherein the universe,but G is not.

A mass attachedto a length of string is moving in a circular path around a central point, O, on a flat, horizontal, frictionless table. This is depicted in the diagram below. The string breaks as the masspassespoint X.

B A

Direction of motion

String I

Which line best depictsthe subsequentpath of the mass? (A)

Line A

(B)

Line B

(C)

Line C

(D)

Line D

What is the main reasonwhy the Michelson-Morley experimentis consideredimportant? (A)

It shows the existenceof the aether.

(B)

It suggeststhat light is an electromagneticwave.

(C)

It indicates that light can exhibit interferenceeffects.

(D)

It provides experimental support for the theory of relativity.

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A stoneis thrown horizontally from the top of a cliff and falls onto the beachbelow. Which acceleration-time graph best describesthe motion of the stone? (A)

(B)

(c)

(D)

Two satellites,X andY, are in circular orbits aroundEarth. Their massesare identical and their orbital radii are R and 16R, respectively. What is the ratio of their orbital periods, T*:Tr?

(A)

I 4

(B) 1 I6

(c) 1 32

\l

u)

(D) 1 64

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The diagram shows a magnet standing on the bottom of a dish filled with a conducting solution. A copper wire is suspendedfreely from a point above the magnet with its tip in the conducting solution. It is held in the position shown. Switch

Pivot

Conducting solution

The switch is closed and the wire released. Which of the following will be observed? (A)

The wire will rotate about the magnet.

(B)

The wire will be attractedto the magnet.

(C)

The magnet will rotate about its vertical axis.

(D)

The solution in the dish will rotate about the magnet.

Dish

A current-cnrying conductor passes through a square region of magnetic field, magnitude 0.5 T, as shown in the diagram. The magnetic field is directed into the page.

What is the magnitudeof the magneticforce on the conductor? (A) 0.170N (B) 0.424N (c)

0.600N

(D) 0.849N

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A squareloop of wire, in a uniform magnetic field, is rotating at a constantrate about an axis as shown. The magnetic freld is directed out of the plane of the page.At time r= 0 the plane of the loop is perpendicularto the magnetic field and side XI is moving out of the page. I Axis

I

r-'\ I

tB

I I I I .l I I

I .l I

Which graph best representsthe variation of the magnetic flux through the loop with time?

(A)

(B)

X fT

(c) 5

(D)

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=

Early electric generatorswere often very simple. A hand-operatedversion is depicted below. Metal disc

Handle

Brush X touchesthe metal axle and Brush I touchesthe rim of the disc. If the metal disc is rotated uniformly as shown, which statement about the current through the globe is correct? (A)

No current flows.

(B)

A direct current flows fromY to X.

(C)

A direct current flows from X to Y.

(D)

An alternating current flows betweenX andY.

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10

The apparatusshown is designedto investigatethe operation of a transformer. Switch

Coil X (100turns) Iron core Coil f (200turns)

A studentclosesthe switch for a short time, then opensit. The data logger recordsvalues of voltage for both coils for the duration of the investigation. The data logger software displays the results as a pair of voltage-time graphs on a computer monitor. Which pair of graphsbest depictsthe student'sresults?

(A) v

(B) v

0

0

(c) v

(D) v

0

0

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11

Lawrence and William Bragg used X-rays to determinethe crystal structureof materials. Which property of waves was the basis of their technique?

12

(A)

Diffraction

(B)

Dispersion

(C)

Polarisation

(D)

Rarefaction

A chargednon-magneticparticle is moving in a magnetic field. What would NOT affect the magnetic force on the particle?

13

(A)

The strength of the magnetic field

(B)

The magnitude of the charge on the particle

(C)

The velocity componentparallel to the magnetic field direction

(D)

The velocity componentperpendicularto the magnetic field direction

The temperatureof a metal is reduced. Which statementcorrectly identifies the changein its electrical resistanceand the reason for this chanse?

14

Electrical resistance

Reason

(A)

lncreases

Metal freezes

(B)

Decreases

More free electronsavailable

(c)

lncreases

Electrons move more slowly

(D)

Decreases

Reducedmetal lattice vibrations

A potential difference of 50 V is applied betweentwo identical, parallel aluminium plates which are separatedby a distanceof 10 mm. In order to double this electric field strength,which new arrangementshould be used? Separation (mm)

Potentialdffirence (Y)

Plates

(A)

20

r00

Aluminium

(B)

5

50

Perspex

(c)

10

100

Copper

(D)

20

50 - 10-

Aluminium

15

When electromagneticradiation shines on metals, photoelectronsmay be emitted. Th maximum kinetic energy of emitted photoelectronsis plotted againstradiation frequenc for four metals as shown in the graph.

AI Fe Be

.o. f r'l

M dA

tr T

x?

\= a

0 .0 0 .2 0 .4 0 .6 0.8 1.0 r .2 1.4 1.6 1.8 2.0 2.2 2.4 Frequency 1l0lsHz;

Electromagneticradiation of wavelength 187 nm shinesupon an unknown metal and the maximum kinetic energyof the photoelectronsis found to ue 2.5 ev. Basedon this information,what is the unknown metal? (A)

AI

(B)

Be

(C)

Ca

(D)

Fe

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