| Syllabus | Alternate Universe Cambridge 0625 |
| Subject | Physics (0625) Extended |
| Paper | 0625/41/O/N/25 · Paper 4, Variant 1 |
| Also listed as | 0625_w25_qp_41 · 0625_w25_ms_41 |
| Session | October/November 2025 |
| Questions | 10, multiple choice, with answers and explanations |
| Cost | Free |
0625/41/O/N/25 answer key
Preview the first questions
Question 1
A train travels at 56 m/s on a level track. The brakes give a uniform deceleration of 1.2 m/s squared. What is the distance the train travels before it stops?
- about 1300 m
- about 47 m
- about 67 m
- about 156 m
Show the answer and explanation
Correct answer: A
Use v squared = u squared - 2 a s with v = 0, so s = u squared / (2 a) = 56 squared / (2 x 1.2) = 3136 / 2.4 = about 1300 m.
Question 2
An object weighs 42 N on Earth, where the gravitational field strength is 9.8 N/kg. On Mars the gravitational field strength is 3.7 N/kg. What is the weight of the same object on Mars?
- about 16 N
- about 42 N
- about 110 N
- about 11 N
Show the answer and explanation
Correct answer: A
Mass is the same everywhere. Mass = weight on Earth divided by g on Earth = 42 / 9.8 = 4.29 kg. Weight on Mars = mass times g on Mars = 4.29 x 3.7 = 15.9, which is about 16 N.
Question 3
A solar cell receives 0.72 kW of light power. The cell has an efficiency of 75%. What is the useful output power?
- 0.54 kW
- 0.96 kW
- 0.18 kW
- 0.72 kW
Show the answer and explanation
Correct answer: A
Useful output power = efficiency as a fraction times the input power = 0.75 x 0.72 = 0.54 kW.
Worked answers: questions 4 to 10
Why each answer is right. The full questions are waiting in every Paperverse world, with your mark at the end.
Question 4 · Answer A
Energy supplied = mass times specific heat capacity times change in temperature = 0.15 x 4200 x (58 - 20) = 0.15 x 4200 x 38 = 23 940 J, which is about 24 000 J.
Question 5 · Answer A
Loudness depends on amplitude: a larger amplitude gives a louder sound. Pitch depends on frequency: a higher frequency gives a higher pitch. Wave X has both a larger amplitude and a higher frequency, so it is louder and has a higher pitch.
Question 6 · Answer A
Using the relation that the sine of the critical angle equals 1 divided by the refractive index: the sine of c = 1 / 1.4 = 0.714. The critical angle is therefore about 46 degrees (45.6 degrees more precisely).
Question 7 · Answer A
Total resistance = supply voltage divided by current = 6.0 / 0.080 = 75 ohms. Since two identical resistors are in series, each has resistance = 75 / 2 = 37.5 ohms, about 38 ohms.
Question 8 · Answer A
The magnetic field of a solenoid is strongest inside the coil, where the field lines run almost parallel and very close together. Close spacing of field lines indicates a strong magnetic field.
Question 9 · Answer A
The proton number is 2, so the nucleus contains 2 protons. The nucleon number is 4, so it has 4 - 2 = 2 neutrons. A neutral atom has the same number of electrons as protons, so there are 2 electrons in shells around the nucleus.
Question 10 · Answer A
Planets follow nearly circular (slightly elliptical) orbits around the Sun. Comets follow highly elliptical orbits, coming very close to the Sun at one end and travelling far out into the Solar System at the other end. Their orbital speed is high near the Sun and low far away.