Year 8 Sound Worksheet - Intermediate

Year 8 Sound worksheet for Year 8 (Key Stage 3 / Year 7-9 (Ages 11-14)). Intermediate level science practice, aligned to the UK National Curriculum. Print-ready with answer key included.

Science•Key Stage 3 / Year 7-9 (Ages 11-14)•Soundintermediate

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Sound in Action: Vibrations, Hearing and Ultrasound

Year 8 Science | Ages 12–13 | Intermediate

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Instructions: Complete the six activities in order, showing your reasoning where a question asks you to explain or calculate. Use the information printed in each activity, and include units in numerical answers where appropriate.

How Sound Travels

Use your understanding of particles and vibrations to answer each question. Give a clear explanation, not just a single word, where asked.

1. A tuning fork is struck and its prongs vibrate. Explain how these vibrations produce a sound that can travel through air to a listener. [3 marks]

2. Sound travels through a solid, a liquid or a gas. What must be present for sound to travel, and why can sound not travel through a vacuum? [2 marks]

3. A sound travels through air and then reaches a wall. Describe how the vibrations are passed from particle to particle through the air. [2 marks]

4. Sound travels faster through steel than through air. Explain this difference in terms of the particles. [2 marks]

Frequency, Amplitude, Pitch and Loudness

Read the data table carefully. Use the frequency values to compare pitch and the amplitude values to compare loudness; do not mix up these two relationships.

Sound	Frequency (Hz)	Amplitude (relative units)
A	200	2
B	800	2
C	200	6
D	500	4

1. Which sound has the highest pitch?

2. Which sound is loudest?

3. Compare sounds A and B. Which property changes, and how does the sound change? [2 marks]

4. Compare sounds A and C. Which property changes, and how does the sound change? [2 marks]

The Ear and Hearing

Use the word bank to complete the sentences about how sound is detected. Each word is used once. Then explain how the brain helps us hear.

Word bank: brain, eardrum, ear canal, ossicles, cochlea

1. Sound waves travel along the ___ and make the ___ vibrate.

2. The three tiny bones called the ___ pass on and amplify the vibrations.

3. Vibrations in the ___ are changed into electrical signals by sensory cells.

4. The signals travel along a nerve to the ___, where they are interpreted as sound.

Echoes and Distance

For these questions, use the speed of sound in air as 340 m/s. For an echo, sound travels to the reflecting surface and back, so the total distance is twice the distance to the surface.

1. A person shouts towards a cliff and hears an echo 2.0 seconds later. Calculate the distance from the person to the cliff. [2 marks]

2. A sound pulse travels 510 m to a wall and reflects back. How long does the full journey take? [2 marks]

3. Explain why a smooth, hard surface is more likely to produce a clear echo than a soft curtain. [2 marks]

Ultrasound: Uses and Evidence

Ultrasound is sound with a frequency above the upper limit of human hearing, about 20,000 Hz. Choose the best answer for each question. Think about how reflected sound waves can provide useful information.

1. Which frequency is ultrasound?

2. In a pregnancy scan, what provides the echoes used to build an image?

3. Why is ultrasound useful for imaging soft tissues?

4. A detector receives an ultrasound echo 0.004 s after a pulse is sent. If sound travels through the material at 1,500 m/s, how far away is the reflecting boundary?

Apply Your Sound Knowledge

Answer each question using precise scientific vocabulary. In the final question, include one appropriate use of ultrasound and explain why it is useful.

1. A guitar string is plucked more strongly but its frequency stays the same. How do the amplitude and loudness change, and what happens to the pitch? [3 marks]

2. A bat uses ultrasound to detect an insect. Explain how the returning sound helps the bat locate the insect. [3 marks]

3. Name one use of ultrasound other than detecting insects, and explain how reflected ultrasound is useful in that application. [3 marks]

Answer Key

Activity 1: 1. The vibrating prongs make nearby air particles vibrate; these particles pass on the disturbance through the air as a sound wave, which reaches the listener. 2. A medium containing particles is needed; a vacuum has no particles to pass on the vibrations. 3. Vibrating particles collide with or push neighbouring particles, passing on the disturbance while particles vibrate about their positions. 4. Steel particles are much closer together, so vibrations are passed between them more quickly than between particles in air.

Activity 2: 1. Sound B. 2. Sound C. 3. Frequency increases from 200 Hz to 800 Hz, so B has a higher pitch; amplitude is unchanged. 4. Amplitude increases from 2 to 6 relative units, so C is louder; frequency is unchanged.

Activity 3: 1. ear canal ; eardrum. 2. ossicles. 3. cochlea. 4. brain.

Activity 4: 1. Total sound journey = 340 × 2.0 = 680 m; distance to cliff = 680 ÷ 2 = 340 m. 2. Total journey time = 1,020 ÷ 340 = 3.0 s. 3. A hard, smooth surface reflects more sound back; a soft curtain absorbs and scatters more sound, making the reflection weaker and less clear.

Activity 5: 1. 40,000 Hz. 2. Sound reflected from structures inside the body. 3. It can reflect at boundaries between different tissues. 4. 3.0 m (total pulse journey = 1,500 × 0.004 = 6 m; distance to boundary = 6 ÷ 2).

Activity 6: 1. Amplitude increases, so loudness increases; pitch stays the same because frequency is unchanged. 2. The bat sends out ultrasound; it reflects from the insect and returns as an echo. The delay and/or direction of the echo helps the bat work out the insect's distance and position. 3. Example: medical imaging. Ultrasound reflects from boundaries between tissues, and the returning echoes are used to build an image. Other valid examples include checking for cracks inside materials or measuring depth underwater, with an accurate explanation of the reflected echoes.