All waves can be described as longitudinal or transverse waves.

Which row of this table best describes sound waves, and water waves on the surface of the sea?

2. Which of these gives a typical range of human hearing?

• A. 200 - 20 000 Hz
• B. 200 - 2 000 Hz
• C. 20 - 20 000 Hz
• D. 20 - 2 000 Hz

3. The space between the Earth and the Sun is a vacuum.

Which row correctly describes the movement of sound and light through a vacuum?

An oscilloscope is a device that can be used to display waves.

Four sound waves are shown here:

Which of these waves is ..

4. .. a loud, high pitched sound?

5. .. a quiet, short wavelength sound?

6-8: Two students carry out an experiment to measure the speed of sound. They hit together two wooden blocks that make a loud sound. An echo can be heard from a wall some distance away.

They record some data for this experiment:

• I. Distance to wall: 50 m
• II. Frequency of sound produced: 400 Hz
• III. Time between original sound and echo: 0.3 s

6. Which of these are needed to calculate the speed of sound?

• A. I and II
• B. I and III
• C. II and III
• D. All three

7. What is their calculated value for the speed of sound?

• A. 166 m/s
• B. 332 m/s
• C. 8 m/s
• D. 120 m/s

8. The students are finding it difficult to time such a short interval between original sound and echo.
Which of these improvements will result in more accurate data?

• A. Move further back from the wall
• B. Hit the blocks harder
• C. Use blocks that make a higher frequency sound
• D. use blocks that make a lower frequency sound

9. Which of these is an electronic device used to detect sound waves and convert them to electrical signals?

• A. a microphone
• B. a loudspeaker
• C. an amplifier
• D. a power supply

10. A sound wave is produced by a musical instrument. Which of the following measurements will not change if a higher pitch note is produced?

• A. frequency
• B. velocity
• C. time period
• D. wavelength