Chapter 6

Do all waves require a medium to propagate? Explain.

What is the difference between a longitudinal wave and a transverse wave? Give an example of each.

What are the SI units for (a) wavelength, (b) frequency, (c) period, and (d) amplitude?

How many values of amplitude are there in one wavelength of a wave, and how is the amplitude related to the energy of a wave?

How are the frequency and the period of a wave related?

With what speed do electromagnetic waves propagate in vacuum?

Which end (blue or red) of the visible spectrum has the longer wavelength? Which has the higher frequency?

Are radio waves sound waves? Explain.

What is a rarefaction?

Which is longer, the wavelength of infrasound or the wavelength of ultrasound?

What is the chief physical property that describes (a) pitch, (b) loudness, and (c) quality?

Can humans hear ultrasound? Give some examples of applications of ultrasound.

Why does the music coming from a band marching in a spread-out formation on a football field sometimes sound discordant?

Why is lightning seen before thunder is heard?

How is the wavelength of sound affected when (a) a sound source moves toward a stationary observer, and (b) the observer moves away from a stationary sound source?

Under what circumstances would sound have (a) a Doppler "blueshift" and (b) a Doppler "redshift"?

Explain why the crack of a whip is a “mini” sonic boom

Radar and sonar are based on similar principles. Sonar (which stands for sound navigation and ranging) uses ultrasound, and radar (which stands for radio detecting and ranging) uses radio waves. Explain the principle of detecting and ranging in these applications.

What is the effect when a system is driven in resonance? Is a particular frequency required? Explain.

Would you expect to find a node or an antinode at the end of a plucked guitar string? Explain.

What determines the pitch or frequency of a string on a violin or a guitar? How does a musician get a variety of notes from one string?