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Jurong Junior College J1 Physics (H2) Common Test

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Name: _________________________ Class: 12S______

Common Test 1 2012

PHYSICS (9646)

Multiple Choice 29th June 2012

1 hour

READ THESE INSTRUCTIONS FIRST

There are thirty-two 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 the given spaces. 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.

(This question paper consists of 15 printed pages inclusive of this one)

JURONG JUNIOR COLLEGE

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Data

speed of light in free space, c = 3.00 108 m s1

permeability of free space, o = 4 107 H m1

permittivity of free space, o = 8.85 1012 F m1

= (1/(36)) 109 F m1

elementary charge, e = 1.60 1019 C

the Planck constant, h = 6.63 1034 J s

unified atomic mass constant, u = 1.66 1027 kg

rest mass of electron, me = 9.11 1031 kg

rest mass of proton, mp = 1.67 1027 kg

molar gas constant, R = 8.31 J K1 mol

1

the Avogadro constant, NA = 6.02 1023

mol1

the Boltzmann constant, k = 1.38 1023 J K1

gravitational constant, G = 6.67 1011 N m

2 kg2

acceleration of free fall, g = 9.81 m s2

Formulae

uniformly accelerated motion, s = ut + 12

at2

v2 = u

2 + 2as

work done on/by a gas, W = p V

hydrostatic pressure, p = gh

gravitational potential, =

Gm

r

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

velocity of particle in s.h.m., v = vo cos t

v =

2 2( )ox x

mean kinetic energy of a molecule of an ideal gas E = 32

kT

resistors in series, R = R1 + R2 + . . .

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

electric potential, V =

o

Q

ε r4

alternating current / voltage, x = xo sin t


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1 Which pair contains one vector and one scalar quantity? A displacement and acceleration

B force and kinetic energy

C momentum and velocity

D power and speed

2 A car is travelling at a velocity of 24 m s-1 due west initially. At a later time, it is seen

travelling at a velocity of 10 m s-1 due south. Given that the direction North N, points vertically upwards, which of the following vectors represents the change in velocity of the car?

3 A student takes 6 readings of the diameter of a rod: 5.9 mm, 6.0 mm, 6.1 mm, 5.8 mm, 6.0 mm, 6.2 mm. The actual diameter of the rod is actually 5 mm. Which of the following best describe the errors in the readings? Random error Systematic error

A low low

B low high

C high low

D high high

4 The quantities p and q are measured with estimated errors of p and q respectively.

Determine the fractional uncertainty in

3q

p

.

A

3

q

q

p

p

B 3)( qp

C q

q

p

p

3

2

1

D qp 32

1

A B C D


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5 The maximum kinetic energy of an electron in the photoelectric effect is given as

KE = hf - . Which statement must be correct for the equation to be homogenous?

A KE, h, f and all have the same units

B KE, h, f and are all scalar quantities

C The product hf has the same units as KE and

D The product hf is numerically equal to ( KE + )

6 A particle undergoes a motion where its displacement, s, varies with time, t, as

shown.

s

t

A graph of the particle’s acceleration, a, plotted over the same interval will look like

7

A lunar landing module is descending to the moon’s surface at a steady velocity of 10.0 m s-1. At a height of 120 m, a small object falls from its landing gear. Assuming that the moon’s gravitational acceleration is 1.60 m s-2, at what speed, in m s-1, does the object strike the moon?

A 202

B 22.0

C 19.6

D 16.8

a a a a

t t t t

A


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8 Two particles P and Q, at the same initial position, accelerates uniformly from rest along a straight line. After 1 s, P is 0.5 m ahead of Q. The separation of P and Q after 2 s from the start is A 0.5 m

B 1.0 m

C 1.5 m

D 2.0 m

9 The velocity-time graph as shown depicts the motion of an object travelling in a

straight line. Which of the following statements is a correct interpretation of the graph?

v/m s-1 10

0 20 40 t/s

A During the first 20 s the object accelerates and travels a distance of 200 m.

B The acceleration of the object increases during the first 20 s to become a maximum when the velocity is 10 m s-1.

C The acceleration of the object when t = 5 s equals the acceleration when t = 35 s.

D The acceleration is zero at t = 20 s. 10 A ball is thrown vertically upwards. It rises to a maximum height X where it is

momentarily at rest. It then falls downwards.

Which of the following statements are true? (i) The acceleration of the ball is always in the same direction as its velocity.

(ii) The acceleration of the ball is always in the opposite direction as its velocity.

(iii) The acceleration of the ball is downwards at all points including X.

(iv) The acceleration of the ball is zero at X.

A (ii) only B (iii) only C (iii) & (iv) only D (i) & (iv) only


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11 Two spheres, A and B, are moving towards each other at speeds 5.0 m s-1 and

2.0 m s-1 respectively as shown below. The mass of sphere B is 5 times the mass of

sphere A.

Given that the collision is elastic, the velocity of B after collision is

A 0.33 m s-1 to the left.

B 0.33 m s-1 to the right.

C 3.0 m s-1 to the left.

D 3.0 m s-1 to the right.

12 A block of mass 1.2 kg slides down a smooth slope from rest as shown in the

diagram.

What is the acceleration of the block along the slope after 2.0 s?

A 3.4 m s2

B 9.0 m s2

C 9.2 m s2

D 9.8 m s2

13 A tennis ball of mass 100 g is struck by a tennis racket. The velocity of the ball is

changed as shown.

What is the magnitude of the impulse of the ball?

A 1.0 kg m s-1

B 5.0 kg m s-1

C 1000 kg m s-1

D 5000 kg m s-1

before collision 5.0 m s-1 2.0 m s-1

A B


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14 A baseball of mass 0.11 kg is thrown with a horizontal velocity of 24 m s1 towards a

batter. After the ball is struck by the bat, it has a speed of 24 m s1 in the direction

60 above the horizontal as shown below.

If the ball and bat are in contact for 0.025 s, the magnitude and direction of the average force exerted on the ball by the bat is

Magnitude Direction

A 106 N

B 106 N

C 180 N

D 180 N


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15 Which of the following statements is untrue about Newton’s Third Law of Motion?

A It involves forces which are equal in magnitude and opposite in direction.

B It involves forces which act on different bodies.

C It involves forces which are of the same nature.

D It involves forces which cancel each other. 16

A driving force F is applied to keep a man moving in constant velocity. If the tension in the cable T and the weight of the man is W, which of the following illustrates the correct equilibrium triangle?

A

B

C

D


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17 Two satellites collide in space inelastically. What happens to the kinetic energy and momentum of the system of the two satellites?

Kinetic energy Momentum

A Conserved Conserved

B Conserved Reduced

C Reduced Conserved

D Reduced Reduced

18 The force-extension graph of a spring is shown in the figure below.

The work done in extending the spring from x1 to x2 is given by

A ½(F1 + F2) (x2 – x1)

B ½(F2 + F1) (x2 + x1)

C ½(F2 - F1) (x2 + x1)

D F2x2 - F1 x1

19 A solid has density 4.0 g cm3. What is the density of a liquid in which the solid would float with one-fifth of its total volume above the liquid surface?

A 0.8 g cm3

B 3.2 g cm3

C 5.0 g cm3

D 20 g cm3


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20 A ladder is leaning against a vertical wall. The wall and ground can be either smooth or rough.

Which of the following options would allow the ladder to be in static equilibrium?

Wall Ground

(i) Smooth Smooth

(ii) Rough Smooth

(iii) Smooth Rough

(iv) Rough Rough

A (iv) only

B (ii) and (iv) only

C (iii) and (iv) only

D (ii), (iii) and (iv) only

21 Which of the following statements is true?

A A couple is a pair of forces which tends to produce rotation in the clockwise direction.

B A couple is a pair of vertical forces which tends to produce rotation only

C A couple is a pair of forces which tends to produce rotation and translational motion.

D A couple is a pair of forces which tends to produce rotation only.

Wall

Ladder

Ground


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22 The diagram shows two identical vessels X and Y connected by a short pipe with a tap.

Initially, X is filled with water of mass m to a depth h, and Y is empty. When the tap is opened, water flows from X to Y until the depths of water in both vessels are equal. How much potential energy is lost by the water during this process? (g = acceleration of free fall)

A 0

B

4

mgh

C

2

mgh

D mgh

23 Two trolleys are placed together on a horizontal runway with a compressed spring

between them.

When they are released, the 2 kg trolley moves to the left at 2 m s-1. How much energy was stored in the spring initially?

A 4 J

B 6 J

C 8 J

D 12 J


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24 A crane lifts a load at constant speed vertically for the first five seconds. It then holds it at a fixed height for another five seconds. The variation of the height of the load above the ground is shown in the graph below. Which of the following shows the power supplied to the load in this process?

A

B

C

D

height above ground/ m

time / s 5 10

s

s

s


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25 What is a reasonable estimate of the gravitational potential energy of a man standing on the fifth storey of a typical HDB flat?

A 1.0 J

B 100 J

C 10 kJ

D 1.0 MJ

( ) ( )

26 A T-34 Russian tank has a mass of 26.5 x103 kg and an engine of power 370 kW that allows it to travel at a maximum speed of 14.7 m s-1 on level ground. What engine power would be required for the tank to move up a slope of 3° with a speed of 8 m s-1? Assume that the total resistive force acting on the tank is the same for all speeds.

A 201 kW

B 310 kW

C 370 kW

D 401 kW

27 Which one of the following sketches best shows the correct relationship between the

thermodynamic temperature (K) and the Celsius temperature (C)?

A

B

C

D

- 273.15


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28 Two thermometers X and Y are placed inside an enclosure whose walls are maintained at a steady temperature T.

When equilibrium is established, X and Y will give the same reading T

A under all circumstances.

B only if they absorb radiation at equal rates.

C only if they have equal thermal capacities.

D only if the enclosure is evacuated.

29 A 1.5 kg metal block at 400 K is placed into a container containing 10 kg of water at 300 K. If the specific heat capacities of water and the metal block are 4200 J K-1 kg-1 and 2499 J K-1 kg-1 respectively, what is their temperature when they have reached thermal equilibrium? Assume the heat capacity of the container is negligible.

A 308 K B 320 K

C 350 K D 700 K

30 Two ideal gases X and Y, are contained in a cylinder at constant temperature. The mass of the atoms of X is m and of Y is 4m.

Which one of the following is the correct value of the ratio

Average kinetic energy of atoms X

Average kinetic energy of atoms Y?

A 1

B 2

C 4

D 16


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31 In the figure below, heat is added to a pure substance in a closed container at a constant rate. A graph of the temperature of the substance as a function of time is shown here.

If Lf is the specific latent heat of fusion and Lv is the specific latent heat of vaporization

of the substance, what is the value of the ratio f

v

L

L for this substance?

A 1.0 B 2.4

C 3.5 D 5.0

32 A sample of an ideal gas may

(i) expand adiabatically (No heat added or removed) or

(ii) expand isothermally (no change in temperature).

The net flow of heat into the gas from the exterior is

A Positive in each case

B Zero for (i) and positive for (ii)

C Zero in both cases

D Negative in both cases

The End

Fig. 31

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