Core · structured questions. Each generated paper follows the 0625 Paper 3 · Theory format, with the same number and style of questions as the real exam, and comes with a Cambridge-style mark scheme.
A car tyre is checked before and after a long journey. The pressure of the air in the tyre is greater after the journey.
(a)
Suggest why the air in the tyre is hotter after the journey.
[1]
(b)
Explain, in terms of molecules, why the pressure increases.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
work done by friction/flexing
friction with the road / flexing of the tyre heats the air B1
1
(b)
faster molecules, more frequent and harder collisions
the molecules have more kinetic energy/move faster B1 they collide with the walls more often B1 and with greater force (change of momentum) B1
3
Question 2Structured · 6 marksA* challenge
Light travels inside a glass fibre of refractive index 1.6.
(a)
Define the critical angle.
[1]
(b)
Calculate the critical angle for the glass.
[2]
(c)
State two conditions for total internal reflection.
[2]
(d)
State one use of optical fibres.
[1]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
angle of incidence for refraction angle 90°
the angle of incidence in the denser medium for which the angle of refraction is 90° B1
1
(b)
38.7°
sin c = 1 ÷ n C1 38.7° A1
2
(c)
denser to less dense; angle > critical
light travels from a denser to a less dense medium B1 angle of incidence is greater than the critical angle B1
2
(d)
communications / endoscope
telecommunications (internet/phone) or endoscopes B1
1
Question 3Structured · 4 marks
A bar magnet is placed on a sheet of paper.
(a)
Describe how to plot the magnetic field lines using a plotting compass.
[3]
(b)
State the direction of the magnetic field lines outside the magnet.
[1]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
mark compass needle positions and join
Any 3 of: place the compass near one pole; mark the position of the needle’s ends; move the compass so its tail is at the last mark and repeat; join the dots to form a field line B3
3
(b)
north to south
from the north pole to the south pole B1
1
Question 4Structured · 4 marks
Railway tracks are laid with small gaps between the rails.
(a)
Explain why the gaps are needed.
[2]
(b)
Explain, in terms of particles, why a solid expands when heated.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
rails expand in hot weather
in hot weather the rails expand B1 without gaps they would push against each other and buckle B1
2
(b)
particles vibrate more, move further apart
particles vibrate with more energy B1 the average separation of the particles increases B1
2
Question 5Structured · 5 marks
Describe the structure of a simple transformer.
(a)
Name the three main parts.
[2]
(b)
Explain how a transformer produces an output voltage.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
primary coil, secondary coil, iron core
Any 2 of: primary coil; secondary coil; soft-iron core (all three = 2) B2
2
(b)
a.c. → changing field in core → induced e.m.f.
alternating current in the primary produces a changing magnetic field B1 the core carries the field to the secondary B1 the changing field induces an e.m.f. in the secondary B1
3
Question 6Structured · 7 marks
A car starts from rest and accelerates uniformly to 15 m/s in 5 s. It then travels at constant speed for 10 s.
(a)
Calculate the acceleration of the car.
[2]
(b)
Calculate the total distance travelled.
[3]
(c)
Calculate the average speed for the whole journey.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
3 m/s²
a = Δv ÷ t C1 3 m/s² A1
2
(b)
188 m
area under speed–time graph C1 ½ × 15 × 5 + 15 × 10 C1 188 m A1
Riyaz Shaikh has mentored IGCSE, IB and A Level students for 15+ years, one-on-one, online and in Mumbai. The hardest questions on this site are the ones he uses to find a student's weak points.
Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in