Waves | AQA A-Level Physics (7408)
Waves
- 191 questions
- 6 subtopics
- Paper 1, and available on Paper 3
- Paper 1 and Paper 3
Waves is examined on Papers 1 and 3.
It covers the properties every wave shares, the stationary waves formed by superposition, and the interference, diffraction and refraction that follow from treating light as a wave.
Sample questions from Waves
Answer each one closed book first, then open the answer.
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Progressive waves
State the wave equation that relates wave speed, frequency and wavelength.
Show the answer
c = fλ, where c is wave speed, f is frequency and λ is wavelength. -
Progressive waves
In a direct-timing method to measure the speed of sound in air, how is the sound pulse generated?
Show the answer
A sharp sound (e.g. a clap or starting pistol) is generated at a measured distance from a detector or observer. -
Longitudinal and transverse waves
What type of wave are electromagnetic waves classified as?
Show the answer
Transverse waves. -
Longitudinal and transverse waves
What does Polaroid material do to light passing through it?
Show the answer
It transmits light oscillating in one plane only and absorbs light oscillating in other planes. -
Principle of superposition of waves and formation of stationary waves
Calculate the frequency when length = 0.5 m, tension = 48 N, mass per unit length = 0.004 kg/m.
Show the answer
Frequency = (1 ÷ (2 × 0.5)) × √(48 ÷ 0.004) = 110 Hz. -
Principle of superposition of waves and formation of stationary waves
What happens to the frequency of a stationary wave on a string if the length of the string is increased, while tension and mass per unit length remain constant?
Show the answer
The frequency decreases. -
Interference
What happens to the waves after they pass through the two slits in Young's experiment?
Show the answer
The waves from the two slits spread out, overlap, and interfere with each other. -
Interference
How can interference of microwaves be demonstrated?
Show the answer
By using two slits or two aerials as coherent sources and detecting maxima and minima with a microwave receiver.
The 6 subtopics
One subtopic is one session. Work down the list.
| Subtopic | What it covers | Questions |
|---|---|---|
| Progressive waves | Amplitude, frequency, wavelength, speed, phase and phase difference, and the wave equation. | 37 |
| Longitudinal and transverse waves | The difference between the two, and why only transverse waves can be polarised. | 17 |
| Principle of superposition of waves and formation of stationary waves | Nodes and antinodes, the harmonics of a string, and the first harmonic formula. | 41 |
| Interference | Coherence and path difference, Young's double slit experiment, fringe spacing, and laser safety. | 45 |
| Diffraction | Single slit diffraction, the grating equation and its derivation, and the orders of maxima. | 27 |
| Refraction at a plane surface | Refractive index and Snell's law, total internal reflection, and optical fibres and dispersion. | 24 |
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Nearby topics
AQA A-Level Physics Active Recall Guide
Every topic, not just this one. 3,682 questions with their answers.