Physics 0625/33 October/November 2025: question paper and mark scheme
Cambridge IGCSE Physics (0625), Paper 3 Core Theory, October/November 2025. Read both free below, or download them. Done the paper? Get it marked by AI against this mark scheme.
Fig. 1.1 shows a stone falling from a cliff to a beach.
cliff stone
beach
Fig. 1.1
(a) Fig. 1.2 shows the speed-time graph for the stone.
35 B
30
speed 25
m/s
20
15
10
5
A
0
0 0.5 1 1.5 2 2.5 3 3.5 4 time / s
Fig. 1.2
(i) Determine the speed of the stone at time = 2.0 s.
speed = …… m / s [1]
(ii) Describe the motion of the stone during section AB of the graph in Fig. 1.2.
…… [1]
(iii) Calculate the distance travelled by the stone between time = 0 and time = 3.4 s.
distance = …… m [3]
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(b) The weight of the stone is 0.12 N.
Calculate the mass of the stone.
mass = …… kg [3]
[Total: 8]
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Mark scheme
1(a)(i) 19.5 (m / s) B1
1(a)(ii) acceleration or speeding up owtte B1
1(a)(iii) 56 (m) A3
½ × 3.4 × 33 C2
(distance =) area under graph or ½ b × h C1
1(b) 0.012 (kg) A3
0.12 ÷ 9.8 C2
(mass =) weight / gravitational field strength or w / g or w / 9.8 C1
(a) A builder uses a metal bar to raise one end of the rock.
builder
rock metal bar
320 N
pivot
1.2 m
Fig. 2.1 (not to scale)
Calculate the moment of the 320 N force about the pivot.
moment = …… Nm [3]
(b) The builder lifts another rock using a truck as shown in Fig. 2.2.
truck
position 2
0.60 m
position 1
Fig. 2.2 (not to scale)
The truck lifts the rock through a vertical height of 0.60 m.
The weight of the rock is 4800 N.
Calculate the work done in lifting the rock.
work done …… J [3]
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(c) The work done by the truck in lifting a different rock is 5800 J.
The truck lifts the rock in a time of 7.4 s.
Calculate the power of the truck in lifting the rock. Include the unit.
power = …… unit …… [4]
[Total: 10]
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Mark scheme
2(a) 380 (Nm) A3
1.2 × 320 C2
(clockwise moment =) force × (perpendicular) distance C1
2(b) 2900 (J) A3
4800 × 0.6 C2
(work done =) force × distance C1
2(c) 780 (W) A3
5800 / 7.4 C2
(power =) work(done) / time or energy / time C1
W or watts B1
(a) A scientist determines the density of a sample of sea water.
Describe an experiment to determine the density of the sea water. You may draw a diagram as part of your answer.
Include any equations in your answer.
…… [4]
(b) Table 3.1 shows the density of four materials.
Table 3.1
density material g / cm3 plastic 0.905 wood 0.720 sea water 1.030
baby oil 0.815
Predict whether solid objects made from plastic or wood float in sea water or baby oil.
Use the data in Table 3.1.
Complete Table 3.2 by writing Yes or No in each space.
Table 3.2
does a plastic does a wooden liquid object float? object float?
sea water
baby oil
[2]
[Total: 6]
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7
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Mark scheme
3(a) any two from: B2
• mass (measured on a) balance
• volume (measured on a) measuring cylinder
• (density =) mass / volume
any two from: B2
• take / find volume of seawater
• take / find mass of ‘container’ (M 1)
• take / find mass of seawater and ‘container’ (M 2)
• subtract masses or M2 – M1
3(b) B1
liquid does a plastic object float? does a wooden object float?
B1
sea water yes yes
baby oil no yes
(a) A teacher shows the class a demonstration about heat energy and states of matter.
The teacher heats a substance. A heater supplies thermal energy at a steady rate. The students measure the temperature of the substance every minute for 30 minutes.
Fig. 4.1 shows the graph of their results.
At point A, the substance is solid.
200
F
150 temperature D E
/ °C
100
B C
50
0 A
0 5 10 15 20 25 30 time / min
Fig. 4.1
(i) Describe the effect of the thermal energy input in section AB of the graph.
…… [1]
(ii) Describe the effect of the thermal energy input in section BC of the graph.
…… [1]
(iii) Determine the temperature at which the substance boils.
…… [1]
(iv) Deduce the state of matter of the substance in section EF of the graph.
…… [1]
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(b) Evaporation is the name of a process that causes puddles of water to dry gradually.
(i) Describe the process of evaporation. Use your ideas about particles.
…… [3]
(ii) Describe another effect that evaporation has on the remaining water in the puddle.
…… [1]
[Total: 8]
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Mark scheme
4(a)(i) temperature increasing or internal energy increasing B1
4(a)(ii) melting or changing from solid to liquid B1
4(a)(iii) 140 (°C) B1
4(a)(iv) Gas B1
4(b)(i) any three from the following: B3
• liquid (particles) → gas / vapour (particles)
• happens at a surface
• (liquid / water absorbs) thermal energy / heat from sun / surroundings / remaining liquid
• (average) kinetic energy of particle increases
• more energetic particles escape owtte
4(b)(ii) (remaining liquid) cools B1
(a) Table 5.1 shows whether some energy resources are renewable and whether they cause air pollution when being used to generate electrical power.
For each energy resource, complete Table 5.1 by writing yes or no in each space. The solar energy resource has been done for you.
Table 5.1
energy resource is it renewable? does it cause air pollution?
solar yes no
fossil fuels
wind
nuclear fuel
tidal
[4]
(b) A solar cell is one way of using the solar energy resource.
Solar cells use visible light from the Sun to generate electrical power.
(i) State the property that allows visible light to travel through space from the Sun to a solar cell.
…… [1]
(ii) A frequency of visible light for a solar cell is 6.0 × 1014 Hz.
The speed of visible light is 3.0 × 108 m / s.
Calculate the wavelength of this visible light.
wavelength = …… m [3]
(c) State one region of the electromagnetic spectrum which has a frequency lower than that of visible light. Describe a use of this region.
region ……
use of the region ……
[2]
[Total: 10]
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Mark scheme
5(a) B1
energy resource is it renewable? does it cause air pollution?
B1
solar yes no
B1
fossil fuels no yes
B1
wind yes no
nuclear fuel no no
tidal yes no
5(b)(i) (light) travels through a vacuum or (light) does not need a medium B1
5(b)(ii) 5(.0) × 10–7 (m) A3
3.0 (× 108) ÷ 6.0 (× 1014) C2
(wavelength =) speed ÷ frequency C1
5(c) infrared or microwaves or radio (waves) B1
matching use B1
Fig. 6.1 shows the path of a ray of visible light travelling from the top of an object and passing through a converging lens.
object
X Y
scale: each square represents 1 cm
Fig. 6.1
(a) State what the line XY represents.
…… [1]
(b) Determine the focal length of the converging lens.
focal length = …… cm [1]
(c) On Fig. 6.1, draw another ray from the object. Continue the path of the ray through the lens until it crosses the path of the ray shown in Fig. 6.1. [2]
(d) On Fig. 6.1, draw an arrow to represent the image. Label it ‘image’. [2]
[Total: 6]
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Mark scheme
6(a) principal axis B1
6(b) 8 (.0) (cm) B1
6(c) ray from top of object to centre of lens M1
ray continued in a straight line to cross drawn ray
or A1
ray from top of object through principal focus on LHS of lens to the centre of the lens
ray continued as a straight paraxial line to cross drawn ray
6(d) upside down (vertical) arrow (labelled image) from principal axis to point where rays cross A2
point where rays cross indicated C1
(a) A student is making a torch.
(i) The torch needs a potential difference (p.d) of 6.0 V. The electromotive force (e.m.f.) of each cell for the torch is 1.5 V.
State the number of cells that the torch needs.
number of cells = …… [1]
(ii) The student has the following components for the electrical part of the torch:
a 6.0 V lamp a switch several 1.5 V cells connecting wire
Draw a circuit diagram to show how the components are connected in series to make the torch. Use standard circuit symbols.
[3]
(b) The p.d. across the lamp is 6.0 V.
The current in the lamp is 0.25 A
(i) Calculate the resistance of the lamp.
resistance = …… Ω [3]
(ii) Calculate the power of the lamp.
power = ……W [3]
[Total: 10]
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Mark scheme
7(a)(i) 4 (cells) B1
7(a)(ii) three (cell (s) / battery, lamp and switch) circuit symbols correct A2
one or two (from cell(s) / battery, lamp and switch) circuit symbols correct C1
a complete circuit with cell (s), lamp and switch in series B1
7(b)(i) 24 (Ω) A3
6(.0) ÷ 0.25 C2
(resistance =) potential difference ÷ current C1
7(b)(ii) 1.5 (W) A3
6(.0) × 0.25 C2
(power =) potential difference × current C1
(a) A coal-fired power station is far from a city. The electricity generated by the power station is transmitted to the city at a high voltage.
State two advantages of high-voltage transmission of electricity.
1 ……
2 ……
[2]
(b) In the city, transformers reduce the high voltage.
Fig. 8.1 shows one of these transformers.
transformer
black cooling fins ground
Fig. 8.1
Transformers become hot when they reduce the high voltage. There are black cooling fins on the casing which contains the transformer.
Explain why the fins are black.
…… [2]
(c) Describe the construction and materials of a simple step-down transformer. You may draw a labelled diagram as part of your answer.
…… [3]
[Total: 7]
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Mark scheme
8(a) any two from: B2
• smaller current (in cables)
• more efficient
• less power / heating losses
• thinner / cheaper cables / pylons further apart owtte
• less voltage drop
• allows for transmission over a longer distance
• fewer / larger power stations can supply more area / whole country
8(b) (black is a) good / best emitter M1
of thermal radiation / infrared A1
8(c) any three from: B3
• two coils
• copper wire / coils
• (coils wrapped round / linked by soft) iron core
• more turns on primary coil
(a) Table 9.1 shows information about particles in an atom.
Complete the table.
Table 9.1
particle charge on particle location of particle positive neutron in the nucleus
negative
[3]
(b) Fig. 9.1 represents three types of emission P, Q and R from a radioactive nucleus. The diagram shows whether each emission can penetrate paper and aluminium.
P
Q
R
thin sheet 5 mm of of paper aluminium
Fig. 9.1
Identify the types of emission labelled P, Q and R.
Type P is ……
Type Q is ……
Type R is ……
[3]
(c) State two precautions for storing radioactive materials safely.
1 ……
2 ……
[2]
[Total: 8]
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Mark scheme
9(a) B1
proton B1
inside the nucleus
neutral / zero / 0 B1
electron outside the nucleus
9(b) P – β / beta (particle) B1
Q – α / alpha (particle) B1
R – γ / gamma (ray) B1
9(c) any two from: B2
• use a lead (lined) box / container or concrete room
• idea of remote / area location / away from main building
• locked room / secure area
• radiation sign on door / in place
• only remove / use for short time owtte
(a) Each box in the left column shows a description of a unit of time.
Each box in the right column shows the name of a unit of time.
Draw a line to connect each description to the appropriate unit.
description name
The time taken for one day the Earth to rotate once on its axis.
one week
The time taken for the Earth to orbit the Sun once. one month
The time taken for the Moon to orbit one year the Earth once.
[3]
(b) (i) The Sun consists mostly of two elements.
State the names of the two elements.
…… and …… [2]
(ii) The Sun radiates energy mostly in three regions of the electromagnetic spectrum. One of these regions is visible light.
State the name for each of the other two regions.
…… and …… [2]
[Total: 7]
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16
Examiners follow the generic marking principles at the front of the scheme, then each question's points: method (M), accuracy (A) and independent (B) marks, error carried forward where the scheme allows it, and positive marking, so you're credited for what you got right.
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Where can I find the 0625/33 October/November 2025 mark scheme?+
On this page, free: the mark scheme for IGCSE Physics 0625/33, October/November 2025 (0625_w25_ms_33), and the question paper (0625_w25_qp_33), to read or download, with each question's marking points written out underneath.
How many marks is 0625/33 out of?+
Physics 0625/33 for October/November 2025 is out of 80 marks, with 1 hour 15 minutes to answer it, across 10 questions.
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Yes. Upload your answers to 0625/33/O/N/25 as a PDF or photos, and CIE Buddy marks every question against this paper's official mark scheme, using Cambridge's marking rules. You get your score, each lost mark explained on your own script, and the topics to revise. It's a guide, not an official Cambridge grade.