Free Superposition questions for AS Level Physics (9702), part of Waves, electricity & particles. Each question has the answer and the marking points an examiner would look for.
Generate a full Superposition worksheet →All Waves, electricity & particles questionsIn a double-slit experiment the slits are 1 m from the screen and the fringe separation is 2.4 mm. The screen is moved a further 0.4 m away from the slits.
What is the new fringe separation?
Answer: D
What is required for two sources to produce an observable stable interference pattern?
Answer: B
Which term is described by this statement?
“Having a constant phase difference.”
Answer: A
A string of length 1.20 m, fixed at both ends, vibrates at 150 Hz forming a stationary wave with three loops.
Calculate the wavelength and the speed of the waves on the string.
Calculate the frequency of the fundamental mode.
State the phase difference between points in adjacent loops.
State the distance between adjacent nodes.
State two differences between a stationary wave and a progressive wave.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | 0.800 m; 120 m s−1 λ = 0.800 m A1 v = 120 m s−1 A1 | 2 |
| (b) | 50 Hz 50 Hz B1 | 1 |
| (c) | 180° 180° (π rad) B1 | 1 |
| (d) | 0.400 m 0.400 m B1 | 1 |
| (e) | energy; amplitude a stationary wave transfers no energy B1 its amplitude varies with position (nodes and antinodes) B1 | 2 |
Light of wavelength 650 nm is incident normally on a diffraction grating with 600 lines per mm.
Calculate the angle of the first-order maximum.
Determine the highest order of maximum that can be observed.
State one advantage of a diffraction grating over a double slit for measuring wavelength.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | 23° d sin θ = nλ with d = 1/600000 C1 23° A1 | 2 |
| (b) | 2 sin θ ≤ 1 so n ≤ d/λ C1 2 A1 | 2 |
| (c) | sharper, brighter maxima; larger angles maxima are sharper/brighter and more widely spaced, so angles can be measured more precisely B1 | 1 |
Light of wavelength 450 nm is incident normally on a diffraction grating with 500 lines per millimetre.
State what is meant by coherent waves.
Explain why a bright first-order maximum is produced at a particular angle.
Calculate the angle of the first-order maximum.
Determine the highest order of maximum that can be observed.
The grating is replaced by one with more lines per millimetre. State and explain the effect on the pattern.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | constant phase difference waves with a constant phase difference B1 | 1 |
| (b) | path difference of one wavelength between adjacent slits; constructive interference waves from adjacent slits have a path difference of one wavelength B1 so they arrive in phase and interfere constructively B1 | 2 |
| (c) | 13.0° d = 1/500 mm = 2.00 × 10−6 m C1 sin θ = λ/d C1 θ = 13.0° A1 | 3 |
| (d) | 4 n = d/λ = 4.44 C1 highest order 4 A1 | 2 |
| (e) | maxima further apart (larger angles); fewer orders d is smaller so sin θ = nλ/d is larger: maxima more widely spaced B1 fewer orders visible B1 | 2 |
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Meet Riyaz →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