The phenomenon of bending of light around obstacles is called:

In a transverse wave, particle motion is:

Resonance occurs when the frequency of an external force matches the:

Waves that require a medium to travel are called:

The Doppler effect refers to the change in:

The range of audible frequencies for a normal human ear is approximately:

Ultrasonic waves have frequencies:

The unit used to measure the loudness of sound is:

Infrasonic waves have frequencies:

Echo is caused by the:

Which characteristic of sound is related to its frequency?