Free Sound questions for IGCSE Physics (0625), part of Waves. Each question has the answer and the marking points an examiner would look for.
Generate a full Sound worksheet →All Waves questionsA student stands between two cliffs and claps once. She hears the first echo 0.8 s after the clap and a second echo 1.6 s after the clap. The speed of sound is 330 m/s.
What is the distance between the two cliffs?
Answer: C
A sound wave becomes louder.
What has changed?
Answer: A
Ultrasound is used to scan unborn babies.
State what is meant by ultrasound.
Explain how ultrasound is used to produce an image.
State how a louder sound and a higher-pitched sound differ from the original sound wave.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | frequency above 20 kHz sound with frequency above 20 000 Hz (above the human hearing range) B1 | 1 |
| (b) | reflections from boundaries timed pulses are reflected at boundaries between tissues B1 the time taken for the echoes is used to find the depth of each boundary B1 | 2 |
| (c) | louder: larger amplitude; higher pitch: higher frequency louder: larger amplitude B1 higher pitch: higher frequency B1 | 2 |
A microphone is connected to an oscilloscope. Fig. 4.1 shows the trace of a sound wave. The time-base is set to 0.5 ms per division.
Use Fig. 4.1 to determine the period of the sound wave.
Use your answer to (a) to calculate the frequency of the sound.
The sound becomes quieter but the pitch stays the same. Describe how the trace changes.
Describe the motion of air particles as the sound wave passes, and explain what is meant by a compression.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | 5.00 ms one wave occupies 10.0 divisions C1 10.0 × 0.5 = 5.00 ms A1 | 2 |
| (b) | 200 Hz f = 1/T = 1/5.00 × 10−3 s C1 200 Hz A1 | 2 |
| (c) | smaller amplitude; same period (same horizontal spacing of the peaks) height of the wave (amplitude) decreases B1 the number of waves across the screen stays the same B1 | 2 |
| (d) | vibrate back and forth parallel to wave direction; compression: region where particles closer together, higher pressure air particles vibrate backwards and forwards B1 parallel to the direction the wave travels B1 a compression is a region where the particles are closer together (higher pressure) B1 | 3 |
A student stands 170 m from a large wall and claps. She hears the echo 1.0 s later.
Calculate the speed of sound in air.
Explain why sound cannot travel through a vacuum.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | 340 m/s distance = 2 × 170 = 340 m C1 speed = 340 m/s A1 | 2 |
| (b) | needs particles to vibrate Any 1 of: sound is a vibration of particles; there are no particles in a vacuum B1 | 1 |
A student measures the speed of sound in air using two microphones connected to a timer.
Describe how the speed is calculated.
Suggest why the microphones should be several metres apart.
State the approximate speed of sound in air.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | distance between microphones ÷ time measure the distance between the microphones B1 divide by the time interval recorded B1 | 2 |
| (b) | longer time, smaller percentage error the time is longer, so the percentage uncertainty is smaller B1 | 1 |
| (c) | 330–350 m/s about 330–350 m/s B1 | 1 |
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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