Lesson T4.1.3

T4.1.3 Echoes and hearing range Quiz: KS3 Physics, Unit 4

20 questions

Written by Revision Ninja · Last reviewed 11 October 2026

In partnership with Revision Ninja

Lesson T4.1.3, Echoes and hearing range: 20 multiple choice questions for the KS3 Physics (National Curriculum), Unit 4: Waves, written with Revision Ninja.

Host it live on the board and students join with a game code on their own devices, or revise alone with Free Play. The answers are revealed in the game.

Host this setFree Play

The 20 questions

  1. What is an echo?

    • A sound wave that is reflected back to the listener from a surface.
    • A sound wave that travels through the ground only and never reaches the listener in the air.
    • A sound wave that is absorbed completely by a surface so that nothing is heard back at all.
    • A light wave that bounces back from a mirror and reaches the eye of the listener quickly.

  2. Why is an echo heard after a short delay?

    • The sound is slowed down by the surface it hits, which delays it on its way back to the ears.
    • The listener's ears take time to process the sound, which delays the echo by a fraction of a second.
    • Echoes are made by a second sound that starts later, which arrives after the first has finished.
    • The sound has to travel to the reflecting surface and back to the listener.

  3. A sound reflects off a wall 170 m away. How long after the sound is made is the echo heard? (Speed of sound is 340 m/s)

    • 1 second
    • 340 seconds, which divides the speed by the distance instead of dividing the distance by the speed
    • 2 seconds, which doubles the time because the sound travels to the wall twice over
    • 0.5 seconds, which uses only the distance to the wall and forgets the return journey

  4. A person shouts and hears an echo 2 seconds later. How far away is the reflecting wall? (Speed of sound is 340 m/s)

    • 170 m, which is the distance travelled by the sound in one direction only and is correct only without the trip back
    • 85 m, which is found by dividing the round trip distance by the speed of the sound
    • 340 m
    • 680 m, which is the total round trip distance and forgets that the wall is only half of it

  5. Which of these surfaces is most likely to produce a clear echo?

    • A carpeted room with soft furnishings, which takes in most of the sound it meets as it goes
    • A pile of loose cushions, which soaks up the sound energy and gives a dull, muffled effect
    • A thick, soft curtain, which absorbs most of the sound rather than reflecting it back
    • A smooth, hard wall

  6. What is meant by sound being absorbed?

    • The sound energy is taken in by the material and is not reflected back.
    • The sound changes into a light wave on the surface, which is then seen rather than heard.
    • The sound speeds up as it passes through the material, which lets it arrive earlier at the ear.
    • The sound is reflected back at a bigger volume, so the material makes the sound louder again.

  7. Why do concert halls have curtains and soft seats?

    • They make the sound travel more slowly through the hall, so the music lasts longer for listeners.
    • They absorb sound, reducing unwanted echoes and reverberation.
    • They reflect all sound back to the stage, which makes the performers easier to hear clearly.
    • They add extra sound energy to the hall, which makes the music sound fuller to the audience.

  8. An echo is heard 4 seconds after a shout. How far away is the reflecting surface? (Speed of sound is 340 m/s)

    • 1360 m, which is the total round trip distance and forgets that the surface is only half of it
    • 340 m, which is the distance the sound travels in one second and ignores the four seconds given
    • 85 m, which divides the round trip distance by the speed of the sound rather than multiplying
    • 680 m

  9. What is the approximate range of hearing for most adult humans?

    • About 1000 Hz to 100 000 Hz, which covers mainly the high sounds and misses the low range
    • About 1 Hz to 1000 Hz, which covers only the low sounds and misses the upper range of hearing
    • About 2 Hz to 200 Hz, which covers only the very lowest rumbles and misses most of the range
    • About 20 Hz to 20 000 Hz

  10. Which animal can hear sounds at frequencies higher than humans can hear?

    • A tortoise, which has very poor hearing and cannot pick up many of the sounds humans hear
    • A cow, which hears a narrower range of sounds than humans do at most frequencies
    • A dog
    • A snail, which has no ears at all and detects sound only through vibrations in the ground

  11. Why do bats use echoes?

    • They hear sounds so low that the echoes are invisible to the human ear and the bat alike.
    • They absorb the echoes to make their voices louder, which helps them call to other bats.
    • They use echoes to heat their wings, which keeps them warm during the flight through the night.
    • They send out high-frequency sounds and use the returning echoes to locate objects.

  12. Why might a sound seem to fade in a large empty hall?

    • The sound is spread out and some of its energy is absorbed by the walls and air.
    • The sound turns into light as it spreads out, which causes the listener to see rather than hear it.
    • Sound becomes heavier in a large space and falls to the floor, so less of it reaches the listener.
    • The sound is reflected back and forth so it gets louder, which makes the hall ring out more.

  13. What must a listener be able to do to hear an echo as a separate sound?

    • Hear the original sound and then the reflected one after a noticeable delay.
    • Hear only sounds with frequencies below 20 Hz, because the echo is too high to be picked up.
    • Stand in the middle of the room with their eyes closed, which lets them focus on the sound alone.
    • Hear the original and reflected sounds at exactly the same time, so they blend into one sound.

  14. Which of these is a good use of ultrasound?

    • Sending radio programmes across the country, which needs high frequency sound to travel far
    • Heating food in a microwave oven, which uses high frequency energy to warm the food quickly
    • Making a loud whistle that a dog can hear, which uses ultrasound to call the dog from afar
    • Cleaning jewellery and scanning babies in the womb

  15. A boat sends a sound pulse down to the seabed and receives the echo 0.5 s later. How deep is the seabed here? (Speed of sound in water is about 1500 m/s)

    • 375 m
    • 750 m, which forgets to halve the round trip distance covered by the pulse to the seabed
    • 187.5 m, which halves the round trip distance a second time after it has already been halved
    • 3000 m, which is found by multiplying the speed by the time and then by the number of trips

  16. What is the minimum distance to a reflecting wall needed to hear a separate echo, if the echo must be heard 0.1 s after the sound is made? (Speed of sound is 340 m/s)

    • About 17 m
    • About 170 m, which assumes that the echo delay should be one second rather than a tenth
    • About 34 m, which forgets to halve the round trip distance covered by the sound
    • About 1.7 m, which divides the round trip distance by ten instead of by two

  17. Which of these is an example of sound being reflected?

    • Feeling a bass drum vibrating in your chest as it is struck during a concert on stage
    • Hearing a whisper only when you stand right next to the speaker who is making the sound
    • Hearing your own voice bounce back from a cliff face
    • Hearing a radio through a thick brick wall, where the sound is absorbed by the bricks

  18. Why does a swimming pool with tiled walls sound echoey?

    • Water stops all sound from being reflected by the walls, so the echoes build up in the air
    • Tiles absorb sound and turn it into light energy that the swimmers can see on the walls
    • Tiles make sound travel slower so that it lingers in the air for a long time after it is made
    • Hard tiles reflect sound strongly, so many echoes overlap.

  19. An echo returns 0.8 s after a sound is made and reflects off a cliff 136 m away. What speed of sound does this imply? (Round trip is 272 m)

    • 340 m/s
    • 170 m/s, which uses only the one-way distance to the cliff and so halves the true speed
    • 272 m/s, which uses the round trip distance directly and does not divide by the time taken
    • 1360 m/s, which divides the round trip by the time and then multiplies the result by four

  20. Which material is best for reducing echoes in a cinema?

    • Bare steel panels, which reflect most of the sound back into the room for every listener
    • Heavy fabric covering the walls and seats
    • Polished marble, which reflects sound strongly from its smooth surface across the whole room
    • Sheets of clear glass, which reflect sound clearly to every corner of the cinema auditorium

All KS3 Physics quizzes