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S2 Science: Sound Waves and Hearing (Paper 1 (basics))
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Tutor Prep Guide · Sound as a longitudinal wave needing a medium, frequency and amplitude, comparing speeds, echo ranging and uses of ultrasound
S2 Science: Sound Waves and Hearing (Paper 1 (basics))
This paper covers the conditions for sound to travel, the separate roles of frequency and amplitude, and one basic speed and echo calculation.
Direct answers Sound needs a medium, frequency sets pitch, amplitude sets loudness, and an echo distance must be halved.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 20 |
| Difficulty mix | Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1 |
| Chapter | Chapter: S2 Science: Sound Waves and Hearing |
| Level | S2 |
02 Questions (10 items)
- FoundationAn alarm bell rings inside a glass jar and the air is pumped out. What happens to the sound?
- FoundationA source vibrates at 50 Hz. What is its period?
- FoundationSound travels at about 340 m/s in air. How far does it go in 2 s?
- IntermediateYou shout at a cliff and hear the echo 2 s later. How far away is the cliff?
- IntermediateWhat frequency range can a human ear normally hear?
- IntermediateIf a source vibrates faster and faster, how does the sound change?
- ChallengeA drum is hit harder so the vibration has a larger amplitude. How does the sound change?
- ChallengeA sound has a frequency of 170 Hz and the speed of sound in air is 340 m/s. What is its wavelength?
- ChallengeThunder is heard 6 s after a lightning flash. Roughly how many kilometres away was it?
- Error redoA student says sound travels through air as a transverse wave. Is that right?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | It becomes almost inaudible because sound needs a medium | Sound is a mechanical wave, so without air or another medium it cannot reach the ear. |
| 2 | 0.02 s | The period is one over the frequency, so 1 divided by 50 gives 0.02 s. |
| 3 | 680 m | Distance is speed times time, so 340 times 2 gives 680 m. |
| 4 | 340 m | The sound travels 680 m in total, and the one way distance is half of that. |
| 5 | About 20 Hz to 20 000 Hz | Below 20 Hz is infrasound and above 20 000 Hz is ultrasound, and neither is heard. |
| 6 | The pitch becomes higher | Faster vibration means a higher frequency, and a higher frequency is heard as a higher pitch. |
| 7 | It becomes louder | Amplitude controls loudness, so a larger vibration gives a louder sound. |
| 8 | 2 m | Wavelength is speed divided by frequency, so 340 divided by 170 gives 2 m. |
| 9 | About 2 km | Sound covers about one third of a kilometre each second, so 6 s is roughly 2 km. |
| 10 | No, sound in air is a longitudinal wave | Air particles vibrate along the direction of travel, which makes it a longitudinal wave. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
For sound questions ask three things: is the journey one way or a round trip, which medium is used, and is the question about frequency or amplitude.Tutor Registration →
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