physics

1. what is equivalent to 2000 microvolts?
a 2ujc" b 2mvv c 2pv d 2000mvv

2 what is the number of si base units required to express electric field strength and power?
electric field
|e | om
a 3 3
b 3 2
cc 4 2
d 4 3

3. the planck constant h has si units js.
which equation could be used to calculate the planck constant?
de — . : :
a h=-—— where dis distance, e is energy and vis velocity
v
boa -7 where vis velocity and d is distance
1
c h=—— where eis electric field strength
4ne
fr2 ’ . , ‘
d h=-—— where fis force, ris radius and mis mass
m

4 two cables are attached to a bracket and exert forces as shown.
bracket 15.0n
a 20.0" ____-- horizontal
i: \6.00n
1 40.0°
vertical
what are the magnitudes of the horizontal and vertical components of the resultant of the two
forces?
horizontal vertical
component/n component/n
a 9.73 0.534
b 9.73 10.2
cc 18.0 0.534
d 18.0 10.2

6 two quantities p and q are directly proportional to each other.
experimental results are taken and plotted in a graph of q against p.
which graph shows there were random errors in the measurements of p and q?
a b cc d
a

7 aman of mass 75.2kg uses a set of weighing scales to measure his mass three times. he
obtains the following readings.
tass |

reading 1 80.2

reading 2 80.1

reading 3 80.2
which statement best describes the precision and accuracy of the weighing scales?
a not precise to + 0.1kg and accurate to + 0.1kg
b_ not precise to + 0.1 kg and not accurate to + 0.1kg
c precise to + 0.1kg and accurate to + 0.1kg
d precise to + 0.1kg and not accurate to + 0.1kg

8 the graph shows how a physical quantity varies with time.
quantity
0
| time
which event could best be represented by the graph?
a the acceleration of a firework rising to a maximum height and falling to the ground
b_ the acceleration of a skydiver leaving an aircraft, falling, opening a parachute and falling to
the ground
c_ the speed of a javelin as it leaves an athlete’s hand, falls and sinks into the ground
d_ the speed of a high jump athlete leaving the ground, jumping over a bar and descending to
the ground

10 a car has mass m. a person needs to pusn the car with force f in order to give the car
acceleration a. the person needs to push the car with force 2f in order to give the car
acceleration 3a.

which expression gives the constant resistive force opposing the motion of the car?
a ma b 2ma c 3ma d 4ma

11 two bar magnets p and q are mounted on floats which can slide without friction along an air
track.
p q
————s ——_
ss n n ss) air track
floats

the two magnets slide towards each other along the air track and interact, without making
contact.
the relative speed of approach of the magnets is equal to their relative speed of separation.
which statement about p and q must be correct?
a during the interaction between p and q some of the total kinetic energy is lost.
b during the interaction between p and q some of the total momentum is lost.
c the momentum of q after the interaction is equal to the momentum of p before the

interaction.
d_ the values of (kinetic energy of p + kinetic energy of q) before and after the interaction are

equal.

12 a submarine descends vertically at constant velocity. the three forces acting on the submarine
are viscous drag, upthrust and weight.
which relationship between their magnitudes is correct?
a_ weight < drag
b_- weight = drag
c_ weight < upthrust
d_ weight > upthrust

13 asmall positive charge can move inside a uniform electric field.
pty,
rss

p q
uniform
electric
field
is} r
pe
the charge moves along different straight paths between points p, q, rand s.
which row gives two paths that result in the same total work done on the charge?
| | path 1 path 2
a ptor qtos
b ptor ptos
cc stoq stor
d s$ toq r to p

14 acar of mass m travels at constant speed up a slope at an angle @ to the horizontal, as shown in
the diagram. air resistance and friction provide a resistive force f. the acceleration of free fall
is g.

sas
meal (6
peat i

what is the force needed to propel the car at this constant speed?
a mgcos@

b mgsing

c mgcosé+f

d mgsinét+f

15 a volume of 1.5m* of water is mixed with 0.50 m° of alcohol. the density of water is 1000 kgm™
and the density of alcohol is 800 kgm.
the volume of the mixture is 2.0m°.
what is the density of the mixture?
a 850kgm® b 900kgm° c 940kgm? d 950kgm*

16 a parachutist is falling at constant (terminal) velocity.
which statement is not correct?
a_ gravitational potential energy is converted into kinetic energy of the air.
b_ gravitational potential energy is converted into kinetic energy of the parachutist.
c_ gravitational potential energy is converted into thermal energy of the air.
d_ gravitational potential energy is converted into thermal energy of the parachutist.

17 a combined heat and power (chp) station generates electrical power and useful heat. the
diagram shows the input and output powers for a chp station.
wasted power
60 mw
bur dower useful heating power
pure 160 mw
from fuel
useful electrical power
100 mw
what is the efficiency of the chp station for producing useful power?
a 31% b 38% c 50% d 81%

18 a bungee jumper jumps off a high bridge, when attached to it by a long elastic rope which obeys
hooke’s law.
the gravitational potential energy of the jumper is measured relative to the lowest point reached
by the jumper.
which graph shows the variation of the gravitational potential energy of the jumper, and the
elastic potential energy in the rope, with the vertical distance fallen from the top of the bridge?
a b

19 a train on a mountain railway is carrying 200 people of average mass 70kg up a slope at an
angle of 30° to the horizontal and at a speed of 6.0ms™. the train itself has a mass of 80000kg.
the percentage of the power from the engine which is used to raise the passengers and the train
is 40%.

what is the power of the engine?
a 1.1mw b 2.83mw c 6.9mw d 14mw

20 awire x is stretched by a force and gains elastic potential energy e.
the same force is applied to wire y of the same material, with the same initial length but twice the
diameter of wire x. both wires obey hooke’s law.
what is the gain in elastic potential energy of wire y?
a 0.25e b 0.5e c 2e d 4e

21 the diagram shows the arrangement of atoms in a particular crystal.
a
s|
ropey
-_
nannies
:
6-----0-----0"
each atom is at the corner of a cube.
the mass of each atom is 3.5 x 10-°kg. the density of the crystal is 9.2 x 10°kgm~.
what is the shortest distance between the centres of two adjacent atoms?
a 3.8x10%m
b 6.2x10%m
c 3.4x10"°m
d 3.0x10°m

22 the stress-strain graphs for loading and unloading four different materials are shown.
which material exhibits purely elastic behaviour?
a b
stress loading stress loading
unloading unloading
0 0
0 strain 0 strain
cc d
stress | loading stress loading
unloading
unloading
0 0
0 strain 0 strain

23 the diagram illustrates the position of particles in a progressive sound wave at one instant in

time.

p q
e e eee e e e e e ® e e eee

ee

the speed of the wave is v. p and q are two points in the wave a distance l apart.

what is an expression for the frequency of the wave?

a ~~ by c mv pl

al ia l v

24 awave moves along the surface of water.
the diagram shows the variation of displacement s with distance along the wave at time ft = 0.
direction of travel
s ,
p
0 distance
0 along wave

which graph best shows the variation with time t of the displacement s of the point p on the
wave?

s
a 0 t

s
b 0 t

s
cc 0 t

s
d 0 t

25 in an experiment to determine the wavelength of sound in air, a stationary wave is set up in an air
column.
the distance between a node and an adjacent antinode is l.
what is the wavelength of the sound?
a $l bol cc 2l d 4l

26 in one of the first experiments to demonstrate the doppler effect, a train was filled with trumpeters
all playing a note of frequency 440 hz. the difference in observed frequency of the note as the
train directly approached a stationary observer was 22 hz. the speed of sound was 340ms™.

at which speed was the train moving?
a 15.4ms" b 16.2ms" cc 17.0ms" d 17.9ms"

27 the electromagnetic spectrum consists of waves with different wavelengths.
which row correctly identifies regions of the electromagnetic spectrum?
[ae [ee [em ||

a microwaves x-rays ultraviolet infrared
b infrared microwaves x-rays ultraviolet
c microwaves infrared ultraviolet x-rays

d x-rays ultraviolet infrared microwaves

28 acathode-ray oscilloscope (cro) is used to display the trace from a sound wave. the time-base
is set at 5usmm.
veer ten
=,
1com
what is the frequency of the sound wave?
a 6.7hz b  67hz c 6.7khz d 67khz

29 monochromatic light is directed at a diffraction grating, as shown.
——_—_—_—_ '
which diagram could show all the possible directions of the light, after passing through the
grating, that give maximum intensity?
a b cc d

30 why can an observable interference pattern never be obtained between two monochromatic
beams of light from different lamps?
a_ the frequency of the light from the two lamps can never be the same.
b_ the light from the two lamps can never be coherent.
c_ the temperature of the filaments of the two lamps used can never be the same.
d_ the wavelength of the light from the two lamps must always be different.

31 a student sets up apparatus to observe the double-slit interference of monochromatic light, as

shown.

monochromatic |

light |
al
double slit
screen

interference fringes are formed on the screen.
which change would increase the distance between adjacent fringes?
a_ decrease the distance between the two slits.
b_ decrease the width of each slit.
c move the screen closer to the double slit.
d_ use light of a higher frequency.

32 an electron is situated in a vacuum between two charged plates, as shown.
°— electron
+ + + + + + + +
which statement describes the motion of the electron due to the uniform electric field?
a_ it moves downwards with a constant acceleration.
b_ it moves downwards with zero acceleration.
c_ it moves upwards with a constant acceleration.
d_ it moves upwards with a decreasing acceleration.

33 a length of wire is connected into a circuit.
area a area 3a
i ————
r is}

the area of the cross-section of the wire changes from a at r to {a at s.

there is a constant current in the wire. charge q passes r in time t.

what is the charge passing point s in the same time t?

a iq b q cc qy2 d 2q

34 four wires are made of the same metal. the cross-sectional areas, lengths and thermodynamic
temperatures of the wires are shown.
which wire has the largest resistance?
| | =|
area
a a 2l 2t
b a l t
cc 2a 2l 2t
d 2a l t

35 a cell with internal resistance is connected to a variable resistor r as shown.
cell
ta
' '
' a '
h h
' '
i '
}
r
the resistance of r is gradually decreased.
how do the current j and the terminal potential difference across the cell change?
terminal potential
current i :
difference across cell

a decreases decreases

b decreases increases

[e increases decreases

d increases increases

et |

36 kirchhoff's first law states that the sum of the currents entering a junction in a circuit is equal to
the sum of the currents leaving it.
the law is based on the conservation of a physical quantity.
what is this physical quantity?
a charge
b_ energy
c mass
d momentum

37 acircuit contains two batteries, each of negligible internal resistance, and two resistors as shown.
9.02
galvanometer
24v 5
3.00 7 x
the galvanometer has a current reading of zero.
what is the electromotive force (e.m.f.) of battery x?
a 6.0v b 8.0v c 16.0v d 18.0v

38 a nucleus of francium-221 (“,,fr) decays into a nucleus of bismuth-209 (“,,bi) in several steps.
which particles could be emitted?
a 2a-particles and 4 b particles
b  2.a-particles and 4 f* particles
c 3.a-particles and 2 8 particles
d 3a-particles and 2 b* particles

39 which equation describes the changes to the quark composition of a nucleus and the lepton
emission during the process of b* decay?
a down — up + positron + electron neutrino
b down — up + positron + electron antineutrino
c up — down + positron + electron neutrino
d up — down + positron + electron antineutrino

40 there are protons, neutrons and electrons in the simple model of an atom.
to which class (group), hadron or lepton, do these particles belong?
p| ratron [teen |

a electron proton and neutron
b neutron proton and electron
cc proton and electron neutron
d proton and neutron electron

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