Waves — AS & A Level Physics (9702) questions by topic
Waves questions order the electromagnetic spectrum by wavelength, resolve a polarised beam's transmitted amplitude, track Doppler-shifted frequency from a swinging child's whistle, and read an oscilloscope's time-base for frequency, marked from 1 to 13 marks.
Calculate, identify and deduce dominate the command words in this A Level Physics topic, with state and draw also common: draw a graph shape correctly rather than sketching a rough zig-zag. 89 real questions from 2023 to 2025 papers are collected below. Submitting each answer for instant marking catches a source-and-observed frequency swapped the wrong way round, or a squared cosine term missed on rearranging, straight away.
What examiners look for
- Examiners note candidates sometimes substitute values incorrectly, confusing the speed of sound with the speed of a train, or swapping observed and source frequencies.
- A common mistake is drawing a curve instead of a straight line, despite starting from the correct point on a graph.
- Reports flag a misconception that a frequency-time graph forms a series of straight lines making a zig-zag shape.
- A recurring criticism is forgetting that a cosine term is squared when rearranging, or substituting incident and transmitted intensities the wrong way round.
- Only the strongest candidates sketch a straight line through the correct points, or the correct overall curve shape for an intensity pattern.
May–June 2025, Paper 11
A surveyor's device emits a pulse of light. The light is reflected from a wall 150 m away. What is the total time taken for the pulse to travel from the device to the wall and…
Answer this question and get it marked →An aircraft produces a sound at a frequency of 30.0 Hz. The speed of sound in air is 330 m s^-1. The aircraft is directly in front of the stationary observer and travels in a…
Answer this question and get it marked →Which statement about longitudinal and transverse wave motion for a progressive wave is correct? A All transverse and longitudinal waves require a medium for propagation. B All…
Answer this question and get it marked →The diagram shows a progressive transverse wave on a stretched string at one instant in time. One point on the string is labelled X. Points A, B, C and D are also marked on the…
Answer this question and get it marked →Which wavelength of electromagnetic radiation in free space could be green light? A 4.9 × 10^-9 m B 6.6 × 10^-9 m C 5.5 × 10^-7 m D 8.6 × 10^-7 m
Answer this question and get it marked →Which group contains only waves that can be polarised? A infrared waves, radio waves, sound waves B visible light waves, microwaves, radio waves C visible light waves, radio…
Answer this question and get it marked →May–June 2025, Paper 12
Radio waves can be used to measure the distance between Earth and the planet Jupiter. A pulse of radio waves is emitted from the surface of Earth. The pulse reflects from the…
Answer this question and get it marked →A sound wave travels from the left to the right. The graph shows the variation of the displacement to the right of particles in the sound wave with distance, at one instant.…
Answer this question and get it marked →A buzzer emitting sound of frequency 846 Hz is attached to a string and rotated in a horizontal circle. The linear speed of the buzzer is 25.0 m s^-1. The speed of sound is 340 m…
Answer this question and get it marked →Vertically polarised light of intensity I₀ is incident normally on a polarising filter. The transmission axis of the filter is at an angle θ to the plane of polarisation of the…
Answer this question and get it marked →Which statement compares the behaviour of transverse and longitudinal waves? A Only longitudinal waves can be diffracted. B Only longitudinal waves can travel in free space. C…
Answer this question and get it marked →May–June 2025, Paper 13
A transverse water wave travels to the right. Three particles on the wave surface are labelled P (at a crest), Q (on the slope between crest and trough), and R (near a point of…
Answer this question and get it marked →Which phenomenon is only associated with transverse waves? A diffraction B interference C polarisation D refraction
Answer this question and get it marked →An oscilloscope displays a wave. The time-base setting is 300 μs per division and the wave occupies 3.5 divisions per cycle. What is the frequency of the wave? A 860 Hz B 950 Hz C…
Answer this question and get it marked →An electromagnetic wave is not visible light. Which wavelength could this wave have? A 4.0 × 10⁻⁷ m B 5.5 × 10⁻⁷ m C 6.5 × 10⁻⁷ m D 8.0 × 10⁻⁷ m
Answer this question and get it marked →May–June 2025, Paper 14
Two progressive waves meet at a fixed point P. The variation with time of the displacement of each wave at point P is shown in the graph. One wave has a larger amplitude than the…
Answer this question and get it marked →A microphone is connected to a cathode-ray oscilloscope (CRO). The y-gain is set to 1 V div⁻¹. The time-base is set to 2.0 ms div⁻¹. The waveform on the display shows…
Answer this question and get it marked →A progressive longitudinal wave is travelling horizontally from left to right. A graphical representation of the wave at one instant in time is shown. Which row could give the…
Answer this question and get it marked →A vehicle is moving with a speed of 30.0 m s⁻¹ directly towards a stationary observer. The horn of the vehicle emits sound of frequency 440 Hz. The speed of sound in air is 340 m…
Answer this question and get it marked →Which row could describe electromagnetic waves? type of wave speed in free space --- --- --- A longitudinal faster for shorter wavelengths B longitudinal the same for all…
Answer this question and get it marked →A horizontal beam of light is incident normally on a polarising filter. The incident light is vertically polarised and has an intensity of 24 W m⁻². The direction of the…
Answer this question and get it marked →May–June 2025, Paper 21
Use the definitions of speed v, frequency f and wavelength λ to derive the wave equation v = fλ.
Answer this question and get it marked →May–June 2025, Paper 22
Two progressive water waves X and Y are shown in Fig. 3.1 (displacement against distance from A). Wave X has amplitude approximately 10.0 cm and wave Y has amplitude approximately…
Answer this question and get it marked →May–June 2025, Paper 23
State why sound waves cannot be polarised.
Answer this question and get it marked →May–June 2025, Paper 24
May–June 2024, Paper 11
A plane wave of amplitude A is incident on a surface of area S placed so that it is perpendicular to the direction of travel of the wave. The energy per unit time reaching the…
Answer this question and get it marked →An electromagnetic wave is travelling through a vacuum. What could be the wavelength and period of the electromagnetic wave? wavelength period --- --- --- A 1.2 × 10⁻¹⁰ Tm 2.5 Ms…
Answer this question and get it marked →The siren of a moving police car emits a sound wave with a frequency of 440 Hz. A stationary observer hears sound of frequency 494 Hz. The speed of sound in the air is 340 m s⁻¹.…
Answer this question and get it marked →The diagram shows the shape at one instant in time of part of a stretched string as a wave travels along it from left to right. Three points 1, 2 and 3 are marked: point 1 on a…
Answer this question and get it marked →Which wave cannot be a longitudinal wave? A a diffracted wave B a polarised wave C a reflected wave D a stationary wave
Answer this question and get it marked →May–June 2024, Paper 12
A man stands stationary in front of a swing. A child sits and swings. The man is at position X to the left; the swing's lowest point is Y; the child swings up to position Z on the…
Answer this question and get it marked →A loudspeaker is playing music in a room. The door to the room is open and has a width of 0.80 m. Sound waves of many different frequencies pass through the doorway and diffract.…
Answer this question and get it marked →A stationary sound wave is set up between a loudspeaker and a wall. A microphone is connected to a cathode-ray oscilloscope (CRO) and is moved along a line directly between the…
Answer this question and get it marked →Polarisation is associated with certain waves. Which waves cannot be polarised? A radio waves from a transmitter B sound waves from a moving source C ultraviolet rays from the Sun…
Answer this question and get it marked →A guitar string is plucked. Which statement describes the resulting waves? A Longitudinal waves on the string cause longitudinal waves in the air. B Longitudinal waves on the…
Answer this question and get it marked →May–June 2024, Paper 13
The diagram shows a representation of a wave on the screen of an oscilloscope. The wave's peak-to-peak height spans 4 cm on the screen. The 1 cm scale marker is shown. The y-gain…
Answer this question and get it marked →A transverse progressive wave on a string has a wavelength of 12 cm and an amplitude of 1.5 cm. The speed of the wave on the string is 48 cm s⁻¹. What is the distance travelled by…
Answer this question and get it marked →An ambulance siren emits a sound with a single frequency f. The ambulance travels towards, passes close to, and then travels away from a stationary observer. Which statement…
Answer this question and get it marked →An electromagnetic wave has a wavelength of 138 pm in a vacuum. To which region of the electromagnetic spectrum does this wave belong? A radio wave B microwave C visible light D…
Answer this question and get it marked →A student investigates the polarisation of microwaves. The microwaves from the transmitter are vertically polarised. A metal grille acts as a polarising filter when placed between…
Answer this question and get it marked →May–June 2024, Paper 23
A progressive transverse wave travelling from left to right is shown at an instant in time in Fig. 4.1. R and T are points on the wave: R is at a crest and T is on the equilibrium…
Answer this question and get it marked →October–November 2024, Paper 11
The graph shows the variation of the displacement with distance for a progressive wave at one instant in time. The displacement is zero at distances of 1.0 cm, 3.0 cm and 5.0 cm,…
Answer this question and get it marked →Which group of electromagnetic waves is arranged in order from shortest wavelength to longest wavelength? A radio waves - visible light - gamma rays B visible light - microwaves -…
Answer this question and get it marked →A wave has a frequency of 5 GHz. What is the period of the wave? A 200 ps B 2 ns C 20 ns D 20 000 micro s
Answer this question and get it marked →Radio waves can be polarised, but sound waves cannot be polarised. Which statement gives the reason for this? A Radio waves are generally of a higher frequency than sound waves. B…
Answer this question and get it marked →October–November 2024, Paper 12
A horizontal beam of vertically polarised light of amplitude A is incident normally on a polarising filter. The transmission axis of the filter is at an angle of 50 degrees to the…
Answer this question and get it marked →A progressive longitudinal sound wave moves through air. The diagram shows the positions of the air particles along part of the wave at one instant. Point Q is a distance x from…
Answer this question and get it marked →An electromagnetic wave in free space has a frequency of 3.0 x 10^16 Hz. Which row gives the principal region of this wave and an example of an electromagnetic wave with a lower…
Answer this question and get it marked →A source of sound emits waves of a constant frequency. The source moves at a constant speed in a straight line relative to a stationary observer. Which velocity of the source…
Answer this question and get it marked →October–November 2024, Paper 13
A source of sound waves of constant frequency is travelling as shown. In which situation would the stationary observer detect a sound with the lowest frequency? A Source moving…
Answer this question and get it marked →Each of the principal radiations of the electromagnetic spectrum has a range of wavelengths. Which wavelength is correctly linked to its radiation? wavelength /m radiation --- ---…
Answer this question and get it marked →A transverse water wave has a frequency of 15 Hz, a wavelength of 0.12 m and an amplitude of 4.0 mm. P is a water particle that is initially at the peak of the wave. What is the…
Answer this question and get it marked →A wave is formed on a string. A student plots a graph of the variation of displacement d with time t for a point on the string. The student marks two points, X and Y, on the…
Answer this question and get it marked →October–November 2024, Paper 22
With reference to the direction of transfer of energy, compare the oscillations of transverse and longitudinal progressive waves.
Answer this question and get it marked →February–March 2023, Paper 12
In a progressive water wave, two particles, P and Q, on the surface of the water, are a fixed horizontal distance apart. P and Q oscillate vertically. At time t = 0, the wave is…
Answer this question and get it marked →Which statement about longitudinal waves and transverse waves is not correct? A Both waves can be polarised. B Both waves can form stationary waves. C Both waves can transfer…
Answer this question and get it marked →An observer hears a sound wave emitted from a moving source. The observed frequency is less than the frequency of sound emitted from the source. What could be the reason for this?…
Answer this question and get it marked →What is the approximate range of frequencies of electromagnetic radiation visible to the human eye? A (430-750) kHz B (430-750) MHz C (430-750) GHz D (430-750) THz
Answer this question and get it marked →A beam of vertically polarised light is incident normally on a polarising filter. The filter can be rotated so that it is always in a plane perpendicular to the beam. The…
Answer this question and get it marked →May–June 2023, Paper 11
The graph shows the variation with time of the displacement of a particle in a progressive wave. Two measurements, x and y, are labelled on the graph: x is the vertical distance…
Answer this question and get it marked →A car travels at a constant speed along a straight line PQ. A loudspeaker attached to the car emits sound of constant frequency f. A stationary observer is at point O, located…
Answer this question and get it marked →Some sources of electromagnetic waves in free space are listed: 1 a radio wave transmitter; 2 a source of X-rays; 3 a 30 mm wavelength radar transmitter; 4 a light-emitting diode…
Answer this question and get it marked →A vertically polarised beam of light is incident normally on a polarising filter. The transmission axis of the filter is at an angle of 40 degrees to the horizontal. What is the…
Answer this question and get it marked →May–June 2023, Paper 12
A longitudinal wave is travelling from left to right. The graph shows the variation of the displacement of the particles with distance along the wave at one instant in time.…
Answer this question and get it marked →A source X emits a sound wave of constant frequency f. The wave is subsequently received at a stationary detector Y. The frequency of the wave that is detected by Y is less than…
Answer this question and get it marked →A beam of visible light is in a vacuum. What could be the frequency of the light? A 5.0 x 10^5 Hz B 5.0 x 10^8 Hz C 5.0 x 10^11 Hz D 5.0 x 10^14 Hz
Answer this question and get it marked →A vertically polarised beam of light of intensity I0 is incident normally on a polarising filter. The transmission axis of the filter is at 45 degrees to the vertical. The beam of…
Answer this question and get it marked →May–June 2023, Paper 13
Graph 1 shows the variation with time of displacement at a fixed distance along a progressive wave; one full cycle spans 0.40 s with amplitude 2.0 cm. Graph 2 represents the same…
Answer this question and get it marked →A vehicle moves with constant velocity along a road directly towards an observer. The observed frequency of the sound from the vehicle changes as the vehicle moves past the…
Answer this question and get it marked →An electromagnetic wave has a wavelength of 2.1 cm in a vacuum. Which region of the electromagnetic spectrum contains this wave? A infrared B microwave C radio wave D visible light
Answer this question and get it marked →A source of plane polarised light is observed through two polarising filters. The filters are positioned so that the source appears at its brightest. One of the filters is then…
Answer this question and get it marked →May–June 2023, Paper 21
An electromagnetic wave in a vacuum has a wavelength of 8.4 x 10^-6 m. State the name of the principal region of the electromagnetic spectrum for the wave.
Answer this question and get it marked →May–June 2023, Paper 22
A progressive wave travels through a medium. The wave causes a particle of the medium to vibrate along a line P. The energy of the wave propagates along a line Q. Compare the…
Answer this question and get it marked →May–June 2023, Paper 23
For a progressive wave, state what is meant by the frequency.
Answer this question and get it marked →October–November 2023, Paper 11
Which row is correct for both progressive transverse waves and progressive longitudinal waves? A transverse: contain compressions and rarefactions; longitudinal: some can travel…
Answer this question and get it marked →A toy drone emits a sound of constant frequency 800 Hz. The speed of the sound in the air is 330 m s^-1. The drone moves along a straight path directly towards an observer and…
Answer this question and get it marked →Which statement about electromagnetic waves in a vacuum is correct? A Infrared waves have shorter wavelengths than visible light waves. B Microwaves have longer wavelengths than…
Answer this question and get it marked →Vertically polarised microwaves are emitted from a source. The microwaves are detected by a receiver connected to a cathode-ray oscilloscope (CRO). The waveform displayed on the…
Answer this question and get it marked →October–November 2023, Paper 12
A transverse wave on a rope has wavelength lambda and period T. The graph shows the variation of the displacement of the particles of the rope with distance in the direction of…
Answer this question and get it marked →A source of sound waves is moving at a constant speed directly towards a stationary observer. The sound waves have a speed of 340 m s^-1 and a frequency of 480 Hz. The observer…
Answer this question and get it marked →A student is investigating two electromagnetic waves, X and Y, in a vacuum. Wave X has a wavelength of 5.2 x 10^-7 m. Wave Y has a frequency of 9.4 GHz. Which principal regions of…
Answer this question and get it marked →A plane polarised light wave of intensity I0 is incident normally on a polarising filter. The initial intensity of the transmitted wave is 0. A second polarising filter is then…
Answer this question and get it marked →October–November 2023, Paper 13
A wave travels on the surface of water. P, Q, R and S are four particles of water on the surface. The diagram shows the positions of the particles at one instant. The direction of…
Answer this question and get it marked →A loudspeaker emits sound of frequency fs. The loudspeaker is attached to a car that moves with increasing speed directly towards a stationary observer. Which statement describes…
Answer this question and get it marked →Which statement about electromagnetic waves in a vacuum is correct? A Amplitude is inversely proportional to velocity. B Frequency is inversely proportional to wavelength. C…
Answer this question and get it marked →A vertically polarised electromagnetic wave of intensity I0 is incident normally on a polarising filter. The transmission axis of the filter is at an angle of 30 degrees to the…
Answer this question and get it marked →October–November 2023, Paper 21
A train travels at a constant high speed along a straight horizontal track towards an observer standing adjacent to the track, as shown in Fig. 5.1. The train sounds its horn…
Answer this question and get it marked →October–November 2023, Paper 22
A beam of vertically polarised light is incident normally on a polarising filter, as shown in Fig. 5.1. The transmission axis of the filter is initially vertical. The filter is…
Answer this question and get it marked →October–November 2023, Paper 23
A train travels at constant speed along a straight horizontal track towards an observer standing adjacent to the track, as shown in Fig. 6.1. The train sounds its horn…
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