Sound and Interference

The number of cycles that are completed per second is called the ________ and is measured in _________.

• frequency, Hertz

• wavelength, meters

• amplitude, meters

• period, seconds

Hertz is the unit for ...

• loudness

• amplitude

• speed of a wave

• frequency

What determines the loudness of a sound?

• Wavelength

• Amplitude

• Crest

• Trough

• Frequency

If a sound wave has a high pitch, it has a ___.

• high frequency

• low frequency

What is changed in the second picture?

• Someone is talking louder in picture 2
• Someone is talking softer in picture 2
• Someone is talking lower pitch in picture 2
• Someone is talking higher pitch in picture 2

If you want to change the pitch of a sound, you have to change the ___

• frequency
• amplitude
• speed
• volume

The Doppler effect causes a sound to appear to have a higher pitch when the source of the sound is:

• Moving towards the observer

• Moving away from the observer

• Stationary relative to the observer

• Rotating around the observer

When a sound wave source moves away from you, what happens to the pitch you hear?

• It increases

• It decreases

• It remains the same

• It fluctuates

What type of interference occurs when two waves meet in such a way that their amplitudes cancel each other out?

• Constructive interference

• Destructive interference

• Refractive interference

• Dispersive interference

Which of the following is true about the speed of sound?

• It is constant in all media

• It is faster in solids than in gases

• It is faster in gases than in liquids

• It is independent of temperature