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Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name and Civics group on the Answer Sheet in the spaces provided. There are forty questions in this paper. Answer all questions. For each question there are four possible answers, A, B, C and D. Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet. Read the instructions on the Answer Sheet very carefully. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet.

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TEMASEK JUNIOR COLLEGE 2012 Mock Preliminary Examination Higher 2

PHYSICS Paper 1 Multiple Choice

9646/01

1 hour 15 minutes

Additional Materials: Multiple Choice Answer Sheet

2

Data speed of light in free space, c = 3.00 x 108 m s-1

permeability of free space, μo = 4π x 10-7 H m-1

permittivity of free space, εo = 8.85 x 10-12 Fm-1

elementary charge, e = 1.60 x 10-19 C

the Planck constant, h = 6.63 x 10-34 J s

unified atomic mass constant, u = 1.66 x 10-27 kg

rest mass of electron, me = 9.11 x 10-31 kg

rest mass of proton, mp = 1.67 x 10-27 kg

molar gas constant, R = 8.31 J K-1 mol-1

the Avogadro constant, NA = 6.02 x 1023 mol-1

the Boltzmann constant, k = 1.38 x 10-23 J K-1

gravitational constant, G = 6.67 x 10-11 N m2 kg-2

acceleration of free fall, g = 9.81 m s-2 Formulae

uniformly accelerated motion, s = ut + ½at2

v2 = u2 + 2as

work done on/by a gas, W = pΔV

hydrostatic pressure, p = ρgh

gravitational potential, φ =

Gmr

−

displacement of particle in s.h.m., x = xo sin ωt

velocity of particle in s.h.m., v = vo cos ωt = ( )22 xxo −± ω

resistors in series, R = R1 + R2 + …

resistors in parallel, 1/R = 1/R1 + 1/R2 + …

electric potential, V = Q / 4πεor

alternating current/voltage, x = xo sin ωt

transmission coefficient, T = exp(-2kd)

where k = ( )2

2

8 m U Eh

π −

radioactive decay, x = xo exp (-λt)

decay constant, λ =

21

693.0t

3

1 The table contains some quantities, together with their symbols and units.

Which expression has the units of energy?

A

gρhV B

hVρg C (ghV D ( g2h

2 The diagram shows the stem of a Celsius thermometer marked to show initial and final

temperature values.

What is the temperature change expressed to an appropriate number of significant figures?

A 14 oC B 20.5 oC C 21 oC D 22.0 oC

3 A projectile is launched at 30o to the horizontal with initial kinetic energy E.

Assuming air resistance to be negligible, what will be the kinetic energy of the projectile when it reaches its highest point?

A 0.25 E B 0.50 E C 0.75 E D 0.87 E

4

4 Which displacement-time graph best represents the motion of a falling sphere, the initial acceleration of which eventually reduces until it begins to travel at constant terminal velocity?

A

B

C D

5 A ball is released from rest above a horizontal surface. The graph shows the variation with time of its velocity.

Areas X and Y are equal.

This is because A the ball’s acceleration is the same during its upward and downward motion.

B the speed at which the ball leaves the surface after an impact is equal to the speed at which it returns to the surface for the next impact.

C for one impact, the speed at which the ball hits the surface equals the speed at which it leaves the surface.

D the ball rises and falls through the same distance between impacts.

5

6 A force F is applied to a trapdoor of mass M at a distance d from the hinge. The force acts at an angle θ to the perpendicular to the door.

Which changes will decrease the magnitude of the moment due to F at the hinge?

A Increase the force F.

B Increase the angle θ.

C Increase the distance d.

D Increase the mass of the trapdoor M.

7 The weight of a solid object is measured with a spring balance. The solid weighs W1 in

air and W2 when totally immersed in a liquid. If the density of the liquid is ρ, what is the volume of the solid?

A

gWW

ρ21 −

B gWW

ρ21 +

C

gW

ρ1 D

gWρ

2

8 A body of mass 1.0 kg is moving at 10 m s-1. A force now acts in its direction of motion.

The variation with time of the force is shown below.

What is the momentum of the body after 6.0 s?

A 20 kg m s-1 B 30 kg m s-1 C 40 kg m s-1 D 50 kg m s-1

t/ s

F/ N

10.0

0 2.0 6.0

6

9 A transport system, used to move luggage from the airport terminal to the aircraft, consists of a powered vehicle connected to four baggage carts by a series of connecting bars.

The mass of the powered vehicle is 200 kg and each of the baggage carts has a mass of 400 kg. The system starts with an acceleration of 2.0 m s–2. What is the tension T in the connecting bar between baggage carts 1 and 2? (Ignore any friction forces on the carts.)

A 800 N B 1200 N C 2400 N D 3600 N

10 The forward motion of a motor-boat is opposed by forces F which vary with the boat’s

speed v in accordance with the relation F = k v2, where k is a constant. The effective power of the propellers required to maintain the speed v is P. Which expression relates k, P and v ?

A

vPk = B 2v

Pk = C 3vPk = D 4v

Pk =

11 The diagram shows a barrel of weight 1.0 x 103 N on a frictionless slope inclined at 30o

to the horizontal.

A force is applied to the barrel to move it up the slope at constant speed. The force is parallel to the slope. What is the work done in moving the barrel a distance of 5.0 m up the slope?

A 1.0 x 104 J B 2.5 x 103 J C 4.3 x 103 J D 5.0 x 103 J

7

12 An aircraft is moving in a horizontal plane at a constant speed. It banks at an angle of 50o to the vertical in order to make a turn as shown below. The only forces acting on the aircraft are lift L and weight W.

What is the ratio of the centripetal force to the weight of the aircraft?

A 0.643 B 0.766 C 0.839 D 1.19

13 The acceleration of free fall on the surface of the Earth is about 6 times its value on the

surface of the Moon. The mean density of the Earth is about 35 times the mean density

of the Moon. Using the data, what is the best value of the ratio of the radius of the Earth to the radius of the Moon?

A 1.9 B 3.2 C 3.6 D 6.0 14 Two stars of equal mass M move with constant speed v in a circular orbit of radius R

about their common centre of mass as shown.

What is the magnitude of the net force on each star?

A

2

2

4RGM

B 2

2

RGM

C R

2Mv 2

D 2RMv 2

50o

W

L

v

R

v

8

15 A spring, fixed at one end, has a mass attached to the other end. The mass bounces up and down. It is shown in the diagram at three positions X, Y and Z.

Which line gives the kinetic, gravitational potential and elastic potential energies?

kinetic energy gravitational potential energy

elastic potential energy

A zero at top maximum at top maximum at top B maximum in centre zero at bottom maximum in centre C zero at bottom zero at bottom zero at top D maximum in centre maximum at top maximum at bottom 16 Which graph best shows how the velocity of an object performing simple harmonic

motion of amplitude a varies with displacement x for one complete oscillation?

A

B

C D

9

17 Let the average translational kinetic energy, at a temperature T, of helium (molar mass 4 g mol−1) be E. The average translational kinetic energy, at the same temperature, of neon (molar mass 20 g mol−1) would be

A 5E. B √5 E. C E. D E/5.

18 Travelling waves of wavelength 20 cm are created in the air columns in a closed pipe P

and an open pipe Q. The lengths of the pipes are shown.

In which pipe or pipes are stationary waves formed?

A P and Q B P only C Q only D Neither P nor Q

19 A plane wave of amplitude A is incident on a surface of area S placed so that it is

perpendicular to the direction of travel of the wave. The energy per unit time reaching the surface is E. The amplitude of the wave is increased to 2 A and the area of the surface is reduced to ½ S. How much energy per unit time reaches this smaller surface?

A 4E B 2E C E D ½ E

20 A diffraction grating with 1000 lines per mm is used to measure the wavelength of

monochromatic light. The angle between the two first order diffraction maxima is 70.0°.

What is the wavelength of the light?

A 287 nm B 470 nm C 574 nm D 940 nm

10

21 Four point charges of equal magnitude Q are placed at the corners of a square as shown below. The centre of the square is at the origin of the x-axis and the y-axis.

At which position, or positions, is the electric potential due to the four point charges equal to zero?

A At the centre of the square only.

B Along the x-axis only.

C Along the y-axis only.

D Along the x-axis and the y-axis.

22 The diagram shows an electron, with charge e, mass m, and velocity v, entering a

uniform electric field of strength E.

The direction of the field and the electron’s motion are both horizontal and to the right. Which expression gives the distance x through which the electron travels before it stops momentarily?

A

Emvx = B

eEmvx = C

2Emvx

2

= D 2eEmvx

2

=

11

23 A cell is connected to a resistor and the current is measured. The graph shows how the current

How much charge passes through the cell during this time?

A 1.50 kC B 4.68 kC C 5.40 kC D 5400 kC

24

A lamp is connected to a power supply of negligible resistance. Which circuit could NOT be used as a practical means to vary the voltage across the lamp?

D

B A

C

12

25 The I-V characteristics of two electrical components P and Q are shown below.

Which statement is correct?

A P is a resistor and Q is a filament lamp.

B The resistance of Q increases as the current in it increases.

C At 1.9 A the resistance of Q is approximately half that of P.

D At 0.5 A the power dissipated in Q is double that in P.

26 The diagram shows a circuit for measuring a small e.m.f. produced by a thermocouple.

There is zero current in the galvanometer when the variable resistor is set at 3.00 Ω.

What is the value of the resistance R?

A 1990 Ω B 990 Ω C 490 Ω D 190 Ω

7.00 Ω

13

27 A common way of investigating charged particles is to observe how they move in a plane at right angles to a uniform magnetic field. The diagram shows the path of a certain particle.

Which of the following gives a satisfactory explanation for the path?

A The momentum of the particle is increasing steadily.

B The charge on the particle is decreasing steadily.

C The magnetic flux density is decreasing steadily.

D The speed of the particle is decreasing steadily.

28 A positively charged oil drop is held stationary between two charged plates as shown

below.

If a magnetic field B directed into the page is now applied, the charged drop would

A move into the page.

B move upwards.

C move to the right.

D stay where it is.

14

29 Three long vertical wires pass through the corners of an equilateral triange PQR. They carry equal currents into or out of the paper in the directions shown in the diagram.

Which diagram shows the direction of the resultant force F on the wire at Q?

A

B

C

D

30 Diagram 1 shows an aluminium rod, moving at right angles to a uniform magnetic field.

Diagram 2 shows the variation with time t of the distance s from O.

Which graph best shows the variation with t of the e.m.f. E induced in the rod?

A B C D

15

31 The primary of an ideal transformer has 200 turns and is connected to a 15 V r.m.s. supply. The secondary has 3200 turns and is connected to a resistor of resistance 120 Ω, as shown in the diagram.

What are the possible values of the secondary voltage, the secondary current and the mean

power dissipated in the resistor?

secondary voltage /V r.m.s.

secondary current /A r.m.s. resistor power/W

A 24 0.020 4.8 B 24 0.20 48 C 240 0.50 120 D 240 2.0 480 32 A lamp of resistance R is connected in series to a source of alternating voltage. The r.m.s.

value of the voltage is 20 V. The variation with time t of the power P dissipated in the light bulb is shown below.

The best estimate for the value of the resistance of the filament of the lamp is

A 4.0 Ω. B 4.0√2 Ω. C 8.0 Ω. D 8.0√2 Ω.

P/W

t/s

16

33 In the photoelectric effect, light incident on a metal surface causes electrons to be ejected from the surface. Which statement is correct?

A Electrons are ejected only if the wavelength of the incident light is greater than some minimum value.

B The de Broglie wavelength of the ejected electrons is the same as the wavelength of the incident light.

C The maximum energy of the ejected electrons is the same as the wavelength of the incident light.

D The maximum energy of the electrons is dependent of the type of metal.

34 An energy level diagram for an atom is shown drawn to scale. The electron transitions

give rise to the emission of a spectrum of lines of wavelength λ1, λ2, λ3, λ4, λ5.

What can be deduced from this diagram?

A λ1 > λ2

B λ3 = λ1 + λ5

C λ4 is the shortest of the five wavelengths.

D The transition corresponding to wavelength λ3 represents the ionisation of the atom.

35 The de Broglie wavelength of an electron accelerated from rest by a potential difference

of 1000 V is λ1. The de Broglie wavelength of another electron accelerated from rest by

a potential difference of 2000 V is λ2. The ratio of 1

2

λλ

is

A 0.50 B 0.71 C 1.4 D 2.0

17

36 X-ray spectra are taken from two X-ray tubes P and Q. The intensity of the X-rays is plotted against the wavelength in both cases and is shown below.

What deduction can be made from these plots?

A X-ray tube Q has the higher voltage applied to it and the target material in both tubes is the same.

B X-ray tube Q has the higher voltage applied to it and the target material in both tubes are different.

C X-ray tube P has the higher voltage applied to it and the target material in both tubes is the same.

D X-ray tube P has the higher voltage applied to it and the target material in both tubes are different.

37 An electron whose total energy 6.0 eV is approaching a barrier whose height is 7.0 eV and

whose thickness is 0.60 nm. What is the probability of the electron tunnelling through the barrier?

A 3.13 x 10-4 B 5.63 x 10-4 C 2.15 x 10-3 D 4.63 x 10-3

18

38 A radioactive nucleus is formed by β-decay. This nucleus then decays by α-emission. Which graph of proton number Z plotted against nucleon number N shows the β-decay followed by the α-emission?

A

B

C

D

40 A radioactive material has a half-life of 4.3 x 107 s.

How many radioactive atoms are present in a source made of this material when it has an activity of 8.7 x 109 Bq?

A 2.0 x 102 B 2.9 x 102 C 3.7 x 1017 D 5.4 x 1017

39 The rest masses of deuteron, proton and neutron are 2.0150 u, 1.0086 u and 1.0097 u respectively.

Given that 1 u = 931 MeV, a deuteron may disintegrate to a proton and a neutron if it

A emits a γ-ray photon of energy 2.0 MeV.

B captures s a γ-ray photon of energy 2.0 MeV.

C emits a γ-ray photon of energy 3.1 MeV.

D captures a γ-ray photon of energy 3.1 MeV.