The number of waves that pass a particular point in a unit of time is called the __________ of the waves. (a) rarefaction (b) compression (c) amplitude (d) frequency



Answer :

MattD
The number of complete waves that pass a given point in a certain amount of time is called the Frequency. If it is cycles per second it is called Hertz.
Xhade
The answer is 
(d) frequency