Question

1.     What is the evidence that sound travels as a wave?

2.     What is the evidence that sound is a form of energy?

3.     When a sound wave passes from air into water, do you expect the frequency or wavelength to change?

Answer 1

1.     The evidence that sound travels as a wave is the fact that its frequency changes as the source of the sound moves relative to the observer.

2.     The evidence that sound is a form of energy is the fact that it can perform work: for example, move objects or make them vibrate.

3.     When a sound wave passes from air into water, I expect that the wavelength will change.