10.8

Question 1

repeated fast, back-and-forth movements

Answer 1

Vibrations

Question 2

the process of pushing material into itself

Answer 2

Compression

Question 3

in sound waves, the layers of air particles that are spread apart (between compressions)

Answer 3

Rarefactions

Question 4

vibrations of particles in the air

Answer 4

Sound Waves

Question 5

number of vibrations in one second, or the number of wavelengths passing in one second

Answer 5

Frequency

Question 6

unit of frequency; its abbreviation is Hz. One hertz is equal to one vibration every second.

Answer 6

Hertz

Question 7

the highness or lowness of a sound. The pitch that you hear depends on the frequency of the vibrating air.

Answer 7

Pitch

Question 8

distance between two neighbouring crests or troughs of a wave. This is the distance between two particles vibrating in step.

Answer 8

Wavelength

Question 9

the maximum distance that a particle moves away from its undisturbed position

Answer 9

Amplitude

Question 10

the longer-lasting sound caused by repeated reflection from hard surfaces

Answer 10

reverberation