Theory past paper questions
Please note that from 2023, Cambridge Theory,
Practical Test and Alternative to Practical examination
questions will expect students to use g = 9.8 N/kg or
9.8 m/s2 in calculations. However, in these past paper
questions g = 10 N/kg or 10 m/s2 is used.
1 Motion, forces and energy
Physical quantities and
measurement techniques, Motion,
Mass and weight and Density
1 A student investigates water dripping from a tap
(faucet).
Fig. T1 shows the dripping tap and a rule next to
a container collecting the drops of water.
i Record the time, in seconds, measured
by the student.
[1]
ii Calculate the average time between
drops of water. Show your working.
[2]
c The student collects drops of water for
15.5 minutes.
Calculate how many drops leave the tap
in 15.5 minutes. Use your answer to
part b ii.
[3]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 32 Q1
May/June 2016
2 Fig. T3 shows a simple pendulum swinging
backwards and forwards between P and Q.
One complete oscillation of the pendulum is when
the bob swings from P to Q and then back to P.
9
10
support
8
tap (faucet)
string
7
rule
5
6
drop of water
3
4
container
2
P
cm
0 1
water
a Name the quantity that the student is
measuring with the rule.
[1]
b The student uses a digital stopwatch to
measure the time between the drops of water.
She repeats her measurement.
Fig. T2 shows the reading on the stopwatch for
all her measurements.
sec
1/100
sec
th
min
00:03 10
time =
▲ Fig. T2
304
th
sec
1/100
sec
min
00:03 04
s
time =
pendulum bob
sec
1/100
sec
a A student starts two stopwatches at the same
time while the pendulum bob is swinging.
The student stops one stopwatch when the
pendulum bob is at P. He stops the other
stopwatch when the pendulum bob next is at Q.
Fig. T4 shows the readings on the
stopwatches.
reading at P
time =
reading at Q
th
00:03 16
s
Q
▲ Fig. T3
▲ Fig.T1
min
R
min
s
1 S
100
0 : 2 . 22
s
▲ Fig. T4
min
s
1 S
100
0 : 2 . 77
Theory past paper questions
3 A person on roller skates makes a journey.
Fig. T5 shows the speed–time graph for the
journey.
X
speed / m / s
Y
10
5
Z
W
0
10
20
30
40
50
60
70
80
90
B
3.0
2.0
100
time / s
▲ Fig. T5
1.0
start of
motion
end of
motion
acceleration
W
X
5.0
10.0
15.0
time / s
20.0
5 a Fig. T7 shows the axes of a distance–time
graph for an object moving in a straight line.
80
distance / m
60
40
20
0
0
2
4 6
time / s
8
10
▲ Fig. T7
deceleration
constant speed
D
0
a Describe the motion of the car in each of
the sections A, B, C and D.
[4]
b Determine the distance moved by the model
car in the first five seconds.
distance =
m
[3]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 32 Q1
May/June 2019
a The graph shows three types of motion.
Copy and complete the table to show when
each type of motion occurs. Use the letters
shown on Fig. T5. Add a letter to each of the
blank spaces.
The first row is done for you.
motion
C
A
▲ Fig. T6
15
0
4.0
0
25
20
b Calculate the distance travelled between
60 s and 100 s.
[3]
c The size of the acceleration is greater than
the deceleration.
Describe how Fig. T5 shows this.
[1]
[Total: 6]
Cambridge IGCSE Physics 0625 Paper 32 Q1
Oct/Nov 2018
4 A student moves a model car along a bench.
Fig. T6 is the speed–time graph for the motion of
the model car.
speed / m / s
i Use readings from Fig. T4 to determine the
time for one complete oscillation of the
pendulum.
time =
s
[2]
ii The method described in a does not
give an accurate value for one complete
oscillation of the pendulum.
Describe how the student could obtain an
accurate value for one complete oscillation
of the pendulum.
[4]
b As the pendulum bob moves from R to Q it
gains 0.4 J of gravitational potential energy.
Air resistance can be ignored.
State the value of kinetic energy of the
pendulum bob at
1. R
2. Q.
[2]
[Total: 8]
Cambridge IGCSE Physics 0625 Paper 32 Q3
May/June 2019
[2]
i 1. O
n a copy of Fig. T7, draw between
time = 0 and time = 10 s, the graph
for an object moving with a constant
speed of 5.0 m/s. Start your graph at
distance = 0 m.
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Theory past paper questions
10
8
6
4
2
40
30
0 10 20 30 40 50 60 70 80 90 100
time / s
[5]
▲ Fig. T10
20
10
0
20
40
60
time / s
80
100
▲ Fig. T8
i The object has an initial speed of 50 m/s
and decelerates uniformly at 0.35 m/s2
for 100 s.
On a copy of Fig. T8, draw the graph to
represent the motion of the object. [2]
ii Calculate the distance travelled by the
object from time = 0 to time = 100 s. [3]
[Total: 9]
Cambridge IGCSE Physics 0625 Paper 42 Q1
May/June 2018
6 Fig. T9 shows students getting on to a school
bus.
b On another part of the journey, the average
speed of the bus is 7.5 m/s.
Calculate the distance the bus travels
[3]
in 150 s.
[Total: 8]
Cambridge IGCSE Physics 0625 Paper 32 Q2
Feb/March 2019
7 a Define acceleration.
[1]
b Fig. T11 shows the distance–time graph for
the journey of a cyclist.
350
300
distance / m
speed / m / s
12
0
50
0
On a copy of Fig. T10, draw the speed–time
graph for this part of the journey made by
the bus.
speed / m / s
2. State the property of the graph that
[2]
represents speed.
ii Between time = 10 s and time = 20 s
the object accelerates. The speed at
time = 20 s is 9.0 m/s.
Calculate the average acceleration
between time = 10 s and time = 20 s. [2]
b Fig. T8 shows the axes of a speed–time
graph for a different object.
250
200
150
100
50
0
0
5 10 15 20 25 30 35 40
time / s
▲ Fig. T11
▲ Fig. T9
a A student describes part of the journey.
The bus accelerates from rest at a constant
rate for 10 s. It reaches a maximum speed of
10 m/s.
The bus maintains a constant speed of 10 m/s
for 60 s.
The bus then decelerates at a constant rate for
15 s, until it stops.
i Describe the motion of the cyclist in the
time between:
1. time = 0 and time = 15 s
2. time = 15 s and time = 30 s
3. time = 30 s and time = 40 s.
[3]
ii Calculate, for the 40 s journey:
1. the average speed
[2]
2. the maximum speed.
[2]
[Total: 8]
Cambridge IGCSE Physics 0625 Paper 42 Q1
Feb/March 2019
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Theory past paper questions
8 Fig. T12 shows a set of masses made from the
same material.
Forces, Momentum, Energy, work
and power and Pressure
10 A load is attached to a spring, as shown in Fig. T14.
Two arrows indicate the vertical forces acting on
the load. The spring and the load are stationary.
support
spring
4.0 N
▲ Fig. T12
a Identify the quantity that is the same for all
the masses.
Choose one box.
 density
 volume
 weight
[1]
b The largest mass is 2.5 kg.
State the number of grams in 2.5 kg.
[1]
c The three largest masses are 2.5 kg, 1.0 kg
and 0.5 kg.
Calculate the combined weight of these three
masses. Include the unit.
[4]
[Total: 6]
Cambridge IGCSE Physics 0625 Paper 32 Q1
Feb/March 2019
9 Fig. T13 shows a wooden raft. The raft is made
from 8 logs.
The logs are all of the same type of wood.
load
▲ Fig. T14
a i State the name of the force acting
vertically downwards.
[1]
ii The vertical force that acts upwards is 4.0 N.
State the value of the force acting
vertically downwards.
[1]
b The load is pulled downwards and then
released. The load moves up and down.
Fig. T15 represents the vertical forces acting
on the load at some time after it is released.
7.6 N
log of wood
2.8 N
▲ Fig. T13
a The average mass of each log is 65.0 kg.
Calculate the total weight of the raft.
[3]
b i The mass of one of the logs is 66.0 kg. It is
3.0 m long and has a cross sectional area of
0.040 m2.
Calculate the density of the wood in the
log.
[3]
ii Explain why the log in b i floats on water.
[1]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 32 Q2
May/June 2018
▲ Fig. T15
Calculate the resultant force on the load and
[2]
state its direction.
c i State the principle of conservation of
[1]
energy.
ii Eventually the load stops moving up and
down.
Describe and explain why the load stops
moving. Use your ideas about conservation
[2]
of energy.
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 32 Q3
Feb/March 2019
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Theory past paper questions
11 a An object is moving in a straight line at
constant speed.
State three ways in which a force may
[2]
change the motion of the object.
b Fig. T16 shows an object suspended from two
ropes. The weight of the object is 360 N. The
magnitude of the tension in each rope is T.
T
T
45º
iii A
heavier child wants to sit on the tyre.
Describe how the tyre position should be
adjusted so that the moment is the same
as in b ii.
[1]
[Total: 8]
Cambridge IGCSE Physics 0625 Paper 31 Q3
May/June 2017
13 Fig. T18 shows the speed–time graph for a
student cycling along a straight, flat road.
45º
8
object
▲ Fig. T16
Determine the tension T by drawing a vector
diagram of the forces acting on the object.
State the scale you have used.
[5]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 42 Q3
Feb/March 2019
12 Fig. T17 shows a tyre hanging from the branch of
a tree.
speed / m / s
360 N
6
4
2
0
0
5
P
15
20
25
30
35
time / s
▲ Fig. T18
a Calculate the distance he travels in the
first 10 s.
b Fig. T19 shows three pairs of forces A, B
and C.
A
2.5 m
10
60 N
20 N
backward force
forward force
[3]
branch
rope
tyre
B
50 N
50 N
backward force
forward force
▲ Fig. T17
a The mass of the tyre is 15 kg.
Calculate its weight.
[2]
b The weight of the tyre exerts a moment on the
branch, about point P where the branch joins
the tree.
i Explain what is meant by the term
moment.
[1]
ii A child sits on the tyre. The weight of the
child and tyre together is 425 N. Calculate
the moment of this force about point P.
Use information given in Fig. T17. Include
the unit.
[4]
C
20 N
70 N
backward force
forward force
▲ Fig. T19
Identify which pair of forces, A, B or C, acts
on the cyclist between 11 s and 16 s. Explain
your choice.
[3]
c The cyclist pushes on one pedal with a force
of 120 N. The area of his shoe in contact with
the pedal is 16 cm2.
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Theory past paper questions
Calculate the pressure on the pedal. Include
the unit.
[4]
[Total: 10]
Cambridge IGCSE Physics 0625 Paper 32 Q2
May/June 2016
14 a The velocity of an object of mass m increases
from u to v.
State, in terms of m, u and v, the change of
[1]
momentum of the object.
b In a game of tennis, a player hits a
stationary ball with his racquet.
i The racquet is in contact with the ball
for 6.0 ms. The average force on the ball
during this time is 400 N.
Calculate the impulse on the tennis ball.[2]
ii The mass of the ball is 0.056 kg.
Calculate the speed with which the ball
leaves the racquet.
[2]
iii State the energy transfer that takes place:
1. as the ball changes shape during the
contact between the racquet and
the ball
2. as the ball leaves the racquet.
[2]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 42 Q3
Oct/Nov 2018
15 Fig. T20 shows a model fire engine. Its brakes
are applied.
model fire engine
containing water tank
jet of water
FIRE
▲ Fig. T20
0.80 kg of water is emitted in the jet every 6.0 s
at a velocity of 0.72 m/s relative to the model.
a Calculate the change in momentum of the
[2]
water that is ejected in 6.0 s.
b Calculate the magnitude of the force acting
on the model because of the jet of water. [2]
c The brakes of the model are released.
State and explain the direction of the
acceleration of the model.
[2]
d In c the model contains a water tank,
which is initially full.
State and explain any change in the
magnitude of the initial acceleration if
the brakes are first released when the
[3]
tank is nearly empty.
[Total: 9]
Cambridge IGCSE Physics 0625 Paper 42 Q2
May/June 2019
16 a A force is used to move an object from the
Earth’s surface to a greater height.
Explain why the gravitational potential
energy (g.p.e.) of the object increases. [1]
b Fig. T21 shows a train moving up towards the
top of a mountain.
▲ Fig. T21
The train transports 80 passengers, each of
average mass 65 kg, through a vertical height
of 1600 m.
Calculate the increase in the total
gravitational potential energy (g.p.e.) of the
passengers.
increase in g.p.e. =
[2]
c The engine of the train has a power of
1500 kW. The time taken to reach the top of
the mountain is 30 minutes.
Calculate the efficiency of the engine in
raising the 80 passengers 1600 m to the top
of the mountain.
[4]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 42 Q2
Feb/March 2018
17 Fig. T22 shows an aircraft on the deck of an
aircraft carrier.
▲ Fig. T22
The aircraft accelerates from rest along the deck.
At take-off, the aircraft has a speed of 75 m/s.
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Theory past paper questions
b Electrical energy from the power station is
used to power two different lamps. Fig. T23
shows how the light outputs from two types
of lamp vary with the power input.
1000
power input to lamp / W
The mass of the aircraft is 9500 kg.
a Calculate the kinetic energy of the aircraft at
take-off.
[3]
b On an aircraft carrier, a catapult provides
an accelerating force on the aircraft. The
catapult provides a constant force for a
distance of 150 m along the deck.
Calculate the resultant force on the aircraft
as it accelerates. Assume that all of the
kinetic energy at take-off is from the work
done on the aircraft by the catapult.
[2]
[Total: 5]
Cambridge IGCSE Physics 0625 Paper 42 Q3
May/June 2018
18 a A nuclear power station generates electrical
energy.
The main stages in the operation of the
nuclear power station are listed.
They are not in the correct order.
E Electrical energy is produced.
F The fission of uranium nuclei releases
thermal energy.
G A turbine drives a generator.
H Thermal energy heats water to produce
steam.
Copy and complete the flow chart to describe
how a nuclear power station works.
In each empty box, insert the letter for the
correct statement.
The nuclear power station uses uranium as a fuel.
filament
lamp
800
600
400
200
0
LED
lamp
0
20
40
60
80
100 120
light output / J / s
▲ Fig. T23
i An experiment requires a lamp with a
light output of 70 J/s.
For the LED lamp and for the filament
lamp determine the input power required
to give a light output of 70 J/s. Use
information from Fig. T23.
1. For the LED lamp, input power =
W
2. For the filament lamp, input
power =
W
[2]
ii Explain why using LED lamps is better for
the environment. Use information from
Fig. T23 in your answer.
[2]
[Total: 6]
Cambridge IGCSE Physics 0625 Paper 32 Q5
May/June 2019
The steam drives a turbine.
Electrical energy is transmitted.
[2]
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Theory past paper questions
19 An archaeologist is investigating a shipwreck
and discovers a wooden box on the seabed.
2 Thermal physics
20 Fig. T25 shows workers pouring liquid metal.
surface of sea
15 m
lid
wooden
box
0.80 m
1.2 m
NOT TO
SCALE
▲ Fig. T24
The dimensions of the lid of the box are 1.2 m by
0.80 m and the pressure of the atmosphere is
1.0 × 105 Pa. The lid is 15 m below the surface
of the sea.
a The density of sea-water is 1020 kg/m3.
Calculate
i the pressure on the lid of the box due
to the sea-water,
[2]
ii the total pressure on the lid,
[1]
iii the downward force that the total
pressure produces on the lid.
[2]
b The force needed to open the lid is not
equal to the value calculated in a iii.
Suggest two reasons for this.
[2]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 42 Q4
May/June 2016
▲ Fig. T25
a The metal changes from hot liquid to cool
solid.
Describe what happens to the arrangement,
separation and motion of the atoms as the
metal changes from hot liquid to cool solid. [3]
b The workers cool their tools in water. They
spill some water onto the floor but later the
floor is dry.
Explain what happens to the water. State the
[3]
name of the process.
[Total: 6]
Cambridge IGCSE Physics 0625 Paper 31 Q6
May/June 2017
21 a Fig. T26 shows the apparatus used to
observe the motion of smoke particles that
are in the air in a box.
eye
microscope
light
air molecules
and
smoke particles
▲ Fig. T26
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Theory past paper questions
[1]
ii Explain why the smoke particle follows
the path that is observed.
[3]
b A tennis player is practising by hitting a ball
many times against a wall.
The ball hits the wall 20 times in 60 s.
The average change in momentum for each
collision with the wall is 4.2 kg m/s.
Calculate the average force that the ball
[3]
exerts on the wall.
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 42 Q5
Feb/March 2018
22 a In Fig. T27, the small circles represent
molecules. The arrows refer to the change of
state from the arrangement of molecules on
the left to the arrangement of molecules on
the right.
X
Y
▲ Fig. T27
Complete the following by writing solid,
liquid or gas in each of the blank spaces.
1. Change of state X is from
to
2. Change of state Y is from
to
[2]
b Explain, in terms of the forces between
their molecules, why gases expand more
than solids when they undergo the same
[2]
rise in temperature.
c A cylinder of volume 0.012 m3 contains a
compressed gas at a pressure of 1.8 × 106 Pa.
A valve is opened and all the compressed
gas escapes from the cylinder into the
atmosphere.
The temperature of the gas does not change.
Calculate the volume that the escaped gas
occupies at the atmospheric pressure of
1.0 × 105 Pa.
[3]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 42 Q7
Feb/March 2019
23 a State and explain, in terms of molecules, any
change in the pressure of a gas when the
volume is reduced at a constant temperature.
[3]
b Copy and complete Table T1 to give the
relative order of magnitude of the expansion
of gases, liquids and solids for the same
increase of temperature.
Write one of these words in each blank space:
gas liquid solid
▼ Table T1
expands most
[2]
expands least
[Total: 5]
Cambridge IGCSE Physics 0625 Paper 42 Q4
May/June 2019
24 A thermometer is used to measure the temperature
inside a room in a house.
a State a physical property that varies
with temperature and can be used in
a thermometer.
[1]
b Fig. T28 shows how the temperature of the
room changes between 6:00 pm and 11:00 pm.
20
temperature / °C
Light from a lamp enters the box through a
window in one side of the box. The smoke
particles are observed using a microscope
fixed above a window in the top of the box.
i The motion of a single smoke particle is
observed through the microscope.
Draw a circle as shown, and sketch the
path of this smoke particle.
15
10
6:00 pm
7:00 pm
8:00 pm
9:00 pm
10:00 pm 11:00 pm
time of day
▲ Fig. T28
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Theory past paper questions
A heater in the room is switched on at 6 pm.
The room has a large window. A large amount of
thermal energy is transferred through the window.
The window in the room has thick curtains.
Closing the curtains reduces the loss of
thermal energy from the room.
i Suggest the time at which the heater is
switched off.
[1]
ii Suggest the time at which the curtains
were closed and explain your answer. Use
information from the graph.
[2]
c In cool climates, people use mineral wool to
reduce heat loss from houses. Mineral wool is
made of fibres and trapped air, as shown in
Fig. T29.
fibres
pocket of trapped air
▲ Fig. T29
Use words from the box to complete the
sentences. Each word may be used once, more
than once, or not at all.
conductor conduction convection
emitter insulator radiation
radiator
.
Air is a good
When air is trapped between fibres, it
reduces heat loss by
and by
. [3]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 32 Q6
Feb/March 2018
25 Fig. T30 shows apparatus used by a student to
measure the specific heat capacity of iron.
a The student improves the accuracy of the
experiment by placing material around the
block, as shown in Fig. T31.
material
▲ Fig. T31
i
S uggest the name of a possible material
the student could use and explain how
it improves the accuracy of the
[3]
experiment.
ii S tate how the student could further improve
the accuracy of the experiment by using
more of the material used in Fig. T31. [1]
b The current in the heater is 3.8 A and
the potential difference (p.d.) across it is
12 V. The iron block has a mass of 2.0 kg.
When the heater is switched on for 10
minutes, the temperature of the block
rises from 25°C to 55°C.
Calculate the specific heat capacity of iron. [4]
[Total: 8]
Cambridge IGCSE 0625 Paper 42 Q4
Oct/Nov 2018
26 a i
A liquid is heated so that bubbles of its
vapour rise to the surface and molecules
escape to the atmosphere.
State the name of this process.
[1]
ii A
t a lower temperature than in a i,
molecules escape from the surface
to the atmosphere.
State the name of this process.
[1]
b i Fig. T32 shows apparatus used to
determine the power output of a heater.
thermometer
thermometer
▲ Fig. T30
electric heater
electric heater
iron block
metal block
▲ Fig. T32
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Theory past paper questions
The metal block has a mass of 2.7 kg.
The metal of the block has a specific
heat capacity of 900 J/(kg °C).
In 2 min 30 s, the temperature of the
block increases from 21°C to 39°C.
Calculate the power of the heater.
[4]
ii State and explain a precaution that can
be taken to improve the accuracy of the
experiment.
[2]
[Total: 8]
Cambridge IGCSE Physics 0625 Paper 42 Q5
May/June 2019
i On a copy of Fig. T34, draw three wavefronts
that have passed through the gap.
[2]
ii State the name of the effect in b i.
[1]
[Total: 5]
Cambridge IGCSE Physics 0625 Paper 32 Q7
Feb/March 2018
28 Fig. T35 shows a ray of light that is reflected by a
mirror.
YZ
ray of
light
mirror
line X
▲ Fig. T35
3 Waves
a i
27 a A ray of light refracts as it travels from air
into glass, as shown in Fig. T33.
ray of
light
air
glass
normal
w
x
y
S tate the name of line X shown on
Fig. T35.
[1]
ii State the name of angle Y shown on
Fig. T35.
[1]
iii A student moves the ray of light and
doubles the size of angle Y. State the
effect on angle Z.
[1]
b Fig. T36 shows a converging lens used to form
an image I of an object O.
object O
z
F
F
▲ Fig. T33
i State which angle w, x, y or z, is the angle
of refraction.
[1]
ii Light is a transverse wave.
State another example of a transverse
wave.
[1]
b Fig. T34 represents some wavefronts
approaching a barrier with a narrow gap.
barrier with
narrow gap
image I
lens
▲ Fig. T36
i State the name of the points labelled F on
Fig. T36.
[1]
ii Describe the nature of the image I.
[2]
[Total: 6]
Cambridge IGCSE Physics 0625 Paper 32 Q6
May/June 2019
29 Fig. T37 represents an object positioned on the
principal axis of a thin lens.
direction of travel
for wavefronts
principal
axis
object
F
F
▲ Fig. T34
▲ Fig. T37
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Theory past paper questions
Each small square of the grid represents 0.5 cm.
Each principal focus of the lens is labelled F.
a Use the grid to determine the focal length of
the lens.
[1]
b i On a copy of Fig. T37, draw a ray from
the top of the object that passes through
a principal focus, then through the lens
and beyond it.
[1]
ii Draw a second ray from the top of the
object that passes through the centre of
the lens. Continue the path of this ray
to the edge of the grid.
[1]
iii Draw an arrow to show the position
and nature of the image produced by
the lens.
[2]
[Total: 5]
Cambridge IGCSE Physics 0625 Paper 32 Q5
May/June 2018
30 a Fig. T38 shows a visible spectrum focused
on a screen by passing light from a source of
white light through a lens and a prism.
glass
lens
glass
prism
screen
i
C opy Fig. T39 and continue the path of
the ray of light up to the end of the
[1]
fibre.
ii The refractive index of the material of
the fibre is 1.46. Calculate the critical
[2]
angle of the material of the fibre.
iii State two uses of optical fibres.
[2]
[Total: 8]
Cambridge IGCSE Physics 0625 Paper 42 Q5
Oct/Nov 2018
31 a A ray of light in glass is incident on a
boundary with air.
State what happens to the ray when the
angle of incidence of the ray is
i less than the critical angle of the glass, [1]
ii greater than the critical angle of the
[1]
glass.
b Fig. T40 shows a ray of light incident on a
glass block at A. The critical angle of the
glass is 41°.
NOT TO
SCALE
air
B
30°
A
A
visible spectrum
B
ray of light
▲ Fig. T40
filament lamp
(white light source)
▲ Fig. T38
i
S tate the name of the process that
separates the colours in white light. [1]
ii State the colour of the light on the
screen at:
point A
point B
[1]
iii State the property of the glass of the prism
that causes white light to be split into the
different colours of the spectrum.
[1]
b Fig. T39 shows a section of an optical fibre
in air. A ray of light is incident on the fibre
wall at X.
X
ray of
light
glass block
optical
fibre
i Copy Fig. T40 and, without calculation,
continue the ray from point B until it
leaves the glass block.
[2]
ii Calculate the refractive index of the
glass.
[2]
[Total: 6]
Cambridge IGCSE Physics 0625 Paper 41 Q6
May/June 2017
32 a Choose two of the following that apply to an
ultrasound wave travelling in air.
frequency 3.5 Hz frequency 350 Hz
frequency 35 000 Hz longitudinal
transverse speed 1.5 m/s
speed 1.5 × 103 m/s speed 1.5 × 106 m/s
[2]
b Calculate the wavelength in a vacuum of
X-rays of frequency 1.3 × 1017 Hz.
[3]
▲ Fig. T39
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Theory past paper questions
c A dentist takes an X-ray photograph of a
patient’s teeth. Explain why it is safe for
the patient to be close to the source of
X-rays, but the dentist must stand away
[2]
from the source.
d State, with a reason, why microwave ovens
are designed only to work with the door
[2]
closed.
[Total: 9]
Cambridge IGCSE Physics 0625 Paper 42 Q6
May/June 2018
33 a A ray of white light is incident on a glass
prism. It forms a spectrum that is visible on
the screen. Fig. T41 shows the arrangement.
narrow slit
ray of white light
ii The types of radiation listed in b i form the
electromagnetic spectrum.
amplitude frequency velocity
Complete the sentence. Choose a word from
the box.
The position of each type of radiation in
the electromagnetic spectrum depends on
its
.
[1]
[Total: 6]
Cambridge IGCSE Physics 0625 Paper 32 Q7
Oct/Nov 2018
34 a Complete the sentences about sound.
Use words from the box above each sentence.
i
glows reflects refracts vibrates
screen
Sound is produced when a source
ii
red
electromagnetic longitudinal transverse
violet
Two of the colours in the visible spectrum are
listed in the box below.
Copy and complete the box. List the five
missing colours of the visible spectrum,
in the correct order.
red
violet
[2]
b Electromagnetic radiation has many uses.
i Draw a line from each use to the type of
radiation it requires.
use
type of radiation
radio waves
Sound waves are
waves.
[1]
metal vacuum liquid
iii
S ound waves cannot travel through
a
.
[1]
b Humans, elephants, mice and dolphins have
different hearing ranges. Fig. T42 shows the
hearing range for each type of animal.
1000 000
100 000
frequency/Hz
▲ Fig. T41
.[1]
10 000
1000
100
10
detecting an intruder at night
microwaves
infra-red
communicating by satellite
for a telephone
humans
elephants
mice
dolphins
▲ Fig. T42
i
S tate the lowest frequency of sound that
can be heard by mice.
[1]
ii State the highest frequency of sound that
can be heard by elephants.
[1]
iii Explain how the chart shows that
elephants can hear some sounds that
humans cannot hear.
[2]
visible light
ultraviolet
detecting broken bones in
the body
0
X-rays
gamma rays
[3]
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Theory past paper questions
iv S tate the term given to the high
frequencies that dolphins can hear but
humans cannot hear.
[1]
[Total: 8]
Cambridge IGCSE Physics 0625 Paper 32 Q8
May/June 2018
35 a A healthy human ear can hear a range of
frequencies.
Three frequency ranges are shown.
Choose the range for a healthy human ear.
0 Hz–20 Hz 10 Hz–10 000 Hz 20 Hz–20 000 Hz [1]
b Explain the meaning of the term ultrasound. [2]
c A student listens to two different sounds,
P and Q.
The two different sounds are represented on a
computer screen on the same scale.
Fig. T43 shows the screens.
sound P
sound Q
▲ Fig. T43
State and explain how sound P is different
from sound Q.
[3]
[Total: 6]
Cambridge IGCSE Physics 0625 Paper 32 Q8
Oct/Nov 2018
4 Electricity and magnetism
ii A small bar of unmagnetised iron is placed
next to a bar magnet, as shown in Fig. T45.
iron
bar
magnet
S
N
▲ Fig. T45
The iron bar moves towards the magnet.
Explain why the iron bar moves.
[2]
b Fig. T46 shows a coil of wire wrapped around
an iron core. A student uses these to make an
electromagnet.
coil
iron core
▲ Fig. T46
i Complete the diagram in Fig. T46 to
show how it could be used to make an
electromagnet.
[1]
ii State one advantage of an electromagnet
compared to a permanent magnet.
[1]
[Total: 5]
Cambridge IGCSE Physics 0625 Paper 32 Q8
May/June 2019
37 a Describe the movement of charge that causes
an object to become positively charged. [1]
b Fig. T47 shows a negatively charged rod
held over an uncharged metal sphere.
negatively
charged rod
36 a Fig. T44 shows the magnetic field pattern
around a bar magnet.
uncharged metal sphere
insulating support
▲ Fig. T47
▲ Fig. T44
i Copy Fig. T44 and mark the North and
South poles of the magnet. Use the letter N
for the North pole and S for the South
pole.
[1]
i On a copy of Fig. T47, add + and – signs
to represent the results of the movement
of charge within the sphere.
[2]
ii Describe the actions that must be taken
to obtain an even distribution of positive
charge on the surface of the sphere. [2]
[Total: 5]
Cambridge IGCSE Physics 0625 Paper 41 Q10
May/June 2017
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Theory past paper questions
nylon thread
negatively charged
polythene rod
negatively charged
polythene rod
▲ Fig. T48
Describe and explain what happens when the
negatively charged rods are close to each
other.
[2]
[Total: 5]
Cambridge IGCSE Physics 0625 Paper 32 Q11
Feb/March 2018
39 a Fig. T49 shows a simple circuit.
A 0.50 A
V
12.0 Ω
40 a The lamp of a car headlight is rated at
12 V, 50 W.
Calculate the current in the lamp when
[2]
operating normally.
b A car is driven at night.
In a journey, the total charge that passes
through the 12 V battery is 270 kC.
i Calculate the electrical energy transferred.
[3]
ii The fuel used by the car provides
3.6 × 104 J/cm3.
Calculate the volume of fuel used to
provide the energy calculated in b i. [2]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 42 Q8
Feb/March 2018
41 Fig. T50 shows current–potential difference
graphs for a resistor and for a lamp.
6.0
4.0
lamp
2.0
resistor
6.0 Ω
▲ Fig. T49
i
b The circuit is changed.
The two resistors are connected in parallel.
Explain what happens, if anything, to the
current reading on the ammeter.
[2]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 32 Q9
May/June 2018
current / V
38 a A student rubs a polythene rod with a dry cloth.
The polythene rod becomes negatively charged.
Describe and explain how the rod becomes
negatively charged.
[3]
b The negatively charged polythene rod hangs
from a nylon thread so that it is free to turn.
The student charges a second polythene rod
and brings it close to the first rod, as shown
in Fig. T48.
T he current in the wires of the circuit is a
flow of particles.
Indicate the name of these particles.
Tick one box.
 electrons
 atoms
 protons
[1]
ii Calculate the combined resistance of the
two resistors.
[1]
iii Calculate the potential difference (p.d.)
reading that would be shown on the
voltmeter.
[3]
0
0
2.0
4.0
6.0
8.0
potential difference / V
▲ Fig. T50
a i The potential difference (p.d.) applied
to the resistor is increased. Choose the
box that indicates the effect on the
resistance of the resistor.
 resistance increases
 resistance is constant
 resistance decreases
[1]
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Theory past paper questions
ii The potential difference (p.d.) applied
to the lamp is increased. Choose the
box that indicates the effect on the
resistance of the lamp.
 resistance increases
 resistance is constant
 resistance decreases
[1]
b The p.d. across the lamp is 6.0 V. Calculate
[2]
the resistance of the lamp.
c The lamp and the resistor are connected in
parallel to a 6.0 V supply.
Calculate the current from the supply. [2]
d The lamp and the resistor are connected in
series to another power supply. The current
in the circuit is 4.0 A.
Calculate the total p.d. across the lamp and
[2]
the resistor.
[Total: 8]
Cambridge IGCSE Physics 0625 Paper 42 Q9
Feb/March 2018
42 Fig. T51 shows a circuit used by a student to test
a metal wire made of nichrome.
ammeter X
A
0.8 A
component Z
ammeter Y
V
A
43 Fig. T52 shows a circuit containing a filament
lamp of resistance 0.30 Ω and two resistors,
each of resistance 0.20 Ω.
0.20 Ω
0.30 Ω
▲ Fig. T52
a Calculate the combined resistance of the
lamp and the two resistors.
[3]
b The potential difference (p.d.) of the supply
is increased so that the current in the lamp
increases.
State and explain any change in the
resistance of the lamp.
[2]
[Total: 5]
Cambridge IGCSE Physics 0625 Paper 42 Q10
May/June 2019
44 a The resistance of a long piece of wire is
6.0 Ω. The potential difference across the wire
is 2.0 V.
Calculate the current in the wire.
[3]
b A force acts on a wire carrying a current in a
magnetic field.
Fig. T53 shows the direction of the current in
the wire and the direction of the force acting
on the wire.
nichrome wire
wire
▲ Fig. T51
a State the name of component Z.
[1]
b The current reading on ammeter X is 0.8 A.
State the reading on ammeter Y.
[1]
c The current in the nichrome wire is 0.8 A. The
potential difference (p.d.) across the nichrome
wire is 4.5 V.
Calculate the resistance of the nichrome
wire.
[3]
d The student tests a different nichrome wire,
which is thicker than the wire in c, but of the
same length. When testing this wire, the current
in the wire is different from the value given in c.
State and explain the difference in current. [2]
[Total: 7]
Cambridge IGCSE 0625 Physics Paper 32 Q10
Oct/Nov 2018
0.20 Ω
current
N
S
direction of force
▲ Fig. T53
i Copy Fig. T53 and draw arrows to indicate
the direction of the magnetic field.
[1]
ii The magnetic field is reversed.
State what happens, if anything, to the
direction of the force on the wire.
[1]
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Theory past paper questions
c Fig. T54 shows a current-carrying coil in a
magnetic field.
magnet
axle
N
N
coil
S
magnet
S
to
+ battery
–
axle
▲ Fig. T54
The coil starts to turn about its axle.
i State two ways of increasing the turning
effect on the coil.
[2]
ii Describe and explain the effect of reversing
the connections to the battery.
[2]
[Total: 9]
Cambridge IGCSE Physics 0625 Paper 32 Q9
May/June 2016
45 Fig. T55 shows two circuits, A and B.
circuit A
circuit B
▲ Fig. T57
State two advantages and two disadvantages
of using wind turbines, rather than fossil
fuels, to generate electricity.
[4]
[Total: 8]
Cambridge IGCSE Physics 0625 Paper 32 Q5
May/June 2016
46 a The resistance of a circuit component varies
with the brightness of the light falling on
its surface.
i State the name of the component.
[1]
ii Draw the circuit symbol for this component.
[1]
b Fig. T58 shows a 6.0 V battery connected
in series with a 1.2 kΩ resistor and a
thermistor.
▲ Fig. T55
Both circuits contain a 6 V power supply and two
6 V lamps.
a State two advantages of circuit B compared
to circuit A.
[2]
b Fig. T56 shows the energy input and outputs,
in one second, for one electric lamp.
energy input
10.0 J
useful energy
output
6.0 V
V
▲ Fig. T58
wasted energy
8.2 J
▲ Fig. T56
i Calculate the useful energy output, in
one second, of the lamp.
ii Draw a labelled diagram, similar to
Fig. T56, for a more efficient lamp.
c Electricity can be generated using wind
turbines.
Fig. T57 shows two wind turbines.
1.2 kΩ
[1]
[1]
i At a certain temperature, the resistance
of the thermistor is 2.4 kΩ.
Calculate the reading on the voltmeter.[4]
ii The battery connected to the circuit in
Fig. T58 is not changed.
Suggest a change that would cause the
reading of the voltmeter to decrease. [1]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 41 Q9
May/June 2017
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Theory past paper questions
47 A student demonstrates electromagnetic induction.
a Describe how to demonstrate electromagnetic
induction using a magnet, a coil of wire and a
sensitive ammeter. You may include a diagram.[3]
b State two factors that affect the size of an
induced electromotive force (e.m.f.).
[2]
[Total: 5]
Cambridge IGCSE Physics 0625 Paper 31, Q12
May/June 2017
48 a The electrical energy produced by a power
station is transmitted over long distances
at a very high voltage.
Explain why a very high voltage is used. [3]
b Fig. T59 represents a transformer.
core
A
120 V ~
P
4000
turns
S 9.0 V
B
▲ Fig. T59
i The primary coil P has 4000 turns and an
input of 120 V. The secondary coil S has
an output of 9.0 V.
Calculate the number of turns in the
secondary coil.
[2]
ii State a suitable material for the core of
the transformer.
[1]
[Total: 6]
Cambridge IGCSE Physics 0625 Paper 42 Q10
Feb/March 2019
5 Nuclear physics
49 Fig. T60 shows a radioactive source placed close
to a radiation detector and counter. The detector
can detect a, β and γ radiation.
radioactive
source
radiation
detector
counter
▲ Fig. T60
The radioactive source emits β-particles only.
Describe how you could show that the source
emits β-particles only.
As part of your answer, you may draw on a copy
of Fig. T60 and add any other apparatus you may
need.
[Total: 4]
Cambridge IGCSE Physics 0625 Paper 32 Q12
Feb/March 2018
50 a A detector of ionising radiation measures the
background count rate in a classroom where
there are no radioactive samples present.
The readings, in counts/minute, taken over
a period of time are shown in this chart.
counts/minute
16
12
14
16
15
17
i State two possible sources of this
background radiation.
[2]
ii Explain why the readings are not the
same.
[1]
b With no radioactive sample present, a
scientist records a background radiation
count of 40 counts/minute.
He brings a radioactive sample close to
the detector. The count rate increases to
200 counts/minute.
After 24 days the count rate is 50 counts/
minute.
Calculate the half-life of the radioactive
sample.
[4]
c On a copy of this chart, draw a line between
each type of ionising radiation and its
property and another line between the
property and its use. One has been done
for you.
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Theory past paper questions
Name of
ionising
radiation
Property
Use
X-ray
It is the most
ionising radiation
and is most easily
absorbed by very
small amounts of
substance
Remotely
detecting leaks
in underground
water pipes
Penetration is
affected by small
changes in the
amount of solid it is
passing through
Detecting
fractures in bones
β-particle
It is highly
penetrating and is
poorly ionising
Detecting smoke
in a fire alarm
system
γ-ray
Can pass easily
through soft living
tissue. Calcium
absorbs more than
soft tissue
Detecting a change
in the thickness
of aluminium
foil during its
manufacture
α-particle
[3]
[Total: 10]
Cambridge IGCSE Physics 0625 Paper 42 Q10
Oct/Nov 2018
51 a A radioactive nucleus of uranium-235 decays to
a nucleus of thorium and emits an a-particle.
Complete the equation.
235
.
U → 
Th + 42a
.
92
[2]
b A nucleus of uranium-235 undergoes nuclear
fission in a reactor.
i State what is meant by nuclear fission. [1]
ii Suggest why a nuclear reactor is
surrounded by thick concrete walls. [2]
iii State one environmental advantage and
one environmental disadvantage of using
a fission reactor to generate electrical
energy in a power station.
[2]
c The thorium produced by the decay in a is also
radioactive and has a half-life of 26 hours.
At a certain time, a pure sample of this
isotope initially contains 4.8 × 109 atoms.
Calculate the number of atoms of this sample
that decay in the following 52 hours.
[3]
[Total: 10]
Cambridge IGCSE Physics 0625 Paper 42, Q11
May/June 2018
52 a A radioactive source is tested over a
number of hours with a radiation detector.
The readings are shown in Table T2.
▼ Table T2
time/
hours
0
detector
reading/
(counts/s)
1
2
3
4
5
6
7
8
9 10
324 96 39 23 21 17 21 20 19 20 18
Use the readings to suggest a value for the
background count-rate during the test, and
to determine the half-life of the sample. [4]
b Hydrogen-3 (tritium) has one proton and two
neutrons. The nucleon number of tritium is
three.
It decays by emitting a β-particle.
Complete the nuclide equation to show this
decay. The symbol X represents the nuclide
produced by this decay.
.
.
.
.
H →
b + 
X [3]
.
.
c The arrows in Fig. T61 show the paths of
three a-particles moving towards gold nuclei
in a thin foil.
gold nucleus
gold nucleus
gold nucleus
▲ Fig. T61
On Fig. T61, complete the paths of the three
a-particles.
[3]
[Total: 10]
Cambridge IGCSE Physics 0625 Paper 41 Q11
May/June 2017
53 Radon-220 is a radioactive isotope.
220
The nuclide notation for radon-220 is 86 Rn.
a Describe the composition of a neutral atom
of radon-220.
[3]
b A nucleus of radon-220 decays to an isotope
of polonium (Po) by emitting an alpha
particle.
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Theory past paper questions
Complete the nuclide equation for the decay
of radon-220.
220
86
Rn → ….a + …..Po
[3]
c A detector of radiation is placed near a
sample of radon-220 and gives a reading of
720 counts/s. The half-life of radon-220 is 55 s.
Calculate the reading after 220 s. Ignore
background radiation.
[2]
[Total: 8]
Cambridge IGCSE Physics 0625 Paper 42 Q11
May/June 2016
c A radioactive substance decays by emitting an
a-particle.
An a-particle can be represented as 42 a .
Draw a labelled diagram showing the
composition of an a-particle.
[3]
[Total: 7]
Cambridge IGCSE Physics 0625 Paper 32 Q12
May/June 2019
54 a Radioactive emission is a random process.
Explain the meaning of the word random. [1]
b The table compares three types of radioactive
emission.
emission
relative ionising ability relative penetrating
ability
alpha
beta
gamma
Complete the table by choosing words from
the box.
high
low
medium
[3]
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