Sound Waves
Learn Sound Waves for GCSE Physics with this free worksheet and full mark scheme — Foundation and Higher exam-style questions with worked answers for AQA, Edexcel and OCR. A separate (triple) physics topic: sound is a longitudinal wave that needs a medium to travel, and humans can typically hear frequencies from 20 Hz to 20 000 Hz.
Free downloads
These worksheets and mark schemes are original, written for Virtus Academy and checked against the current AQA, Edexcel and OCR specifications. Every worksheet comes with a full mark scheme.
This is a Higher tier only topic, so there's no Foundation paper — only the Higher worksheet and mark scheme below.
Topic overview
Sound waves are longitudinal, and they travel through solids by causing vibrations in the solid. This is a Triple-only and Higher-only topic.
The conversion of sound waves to vibrations in solids is how sound is transmitted through them. This works over a limited frequency range, which is why solids transmit some sounds better than others.
Hearing depends on the ear converting sound waves into vibrations. Sound waves cause the eardrum and other parts of the ear to vibrate, and these vibrations are converted into electrical signals sent to the brain. The normal human hearing range is 20 Hz to 20 000 Hz, and this range is restricted by the conversion mechanism in the ear.
Revision notes
Sound in solids
Sound waves travel through solids by causing vibrations in the solid.
This conversion works over a limited frequency range, which depends on the properties of the solid. Sound travels faster in solids than in air because the particles are closer together.
How we hear
Sound waves cause the eardrum and other parts of the ear to vibrate.
These vibrations are converted into electrical signals which are sent to the brain. The mechanism restricts hearing to a limited frequency range.
The hearing range
The normal human hearing range is 20 Hz to 20 000 Hz.
This range is limited by the conversion of sound waves to vibrations within the ear. Frequencies above 20 000 Hz are called ultrasound.
Key points
- Sound waves are longitudinal.
- Sound travels through solids by causing vibrations.
- Conversion works over a limited frequency range.
- The eardrum vibrates when sound reaches it.
- Vibrations are converted to electrical signals.
- Human hearing range is 20 Hz to 20 000 Hz.
Worked examples
Example 1
State the normal range of human hearing. [2 marks]
Model answer
From 20 Hz (1 mark) to 20 000 Hz (1 mark).
Example 2
Explain how sound waves are detected by the human ear. [3 marks]
Model answer
Sound waves cause the eardrum and other parts of the ear to vibrate (1 mark). These vibrations are converted into electrical signals (1 mark), which are sent to the brain and interpreted as sound (1 mark).
Example 3
Explain why human hearing is limited to a particular frequency range. [2 marks]
Model answer
Hearing depends on the conversion of sound waves into vibrations within the ear (1 mark), and this conversion only works effectively over a limited range of frequencies (1 mark).
Common mistakes
Saying sound is a transverse wave.
Sound waves are longitudinal.
Giving the hearing range in kilohertz incorrectly.
It is 20 Hz to 20 000 Hz, which is 0.02 kHz to 20 kHz.
Saying sound travels slower in solids.
It travels faster in solids because the particles are closer together.
Forgetting the conversion to electrical signals.
The brain receives electrical signals, not sound waves.
Exam tips
- Learn the 20 Hz to 20 000 Hz range precisely.
- Describe hearing as a chain: waves, vibrations, electrical signals, brain.
- State that sound is longitudinal.
- Remember this is Triple-only AND Higher-only.
Key terms
- Longitudinal
- Oscillations parallel to the direction of energy transfer.
- Eardrum
- The membrane that vibrates when sound reaches the ear.
- Hearing range
- 20 Hz to 20 000 Hz for normal human hearing.
- Ultrasound
- Sound above 20 000 Hz, beyond human hearing.
Related topics
Written and reviewed against the current AQA, Edexcel and OCR specifications. Spotted an error? Let us know.