Sound Waves

Abstract

Recall that the first step in an acoustical event is a vibration of some kind and the second step is the propagation of that vibration. The opening chapters of this book introduced vibrations. Now it is time to look at that second step. Vibrations are propagated by means of sound waves. Therefore, this propagation raises the topic of waves themselves. As you know, there are many different kinds of waves—radio waves, light waves, X-rays, and waves on the surface of a lake. Sound waves are another important example. The different waves have some common features. They all have some frequency (or frequencies). They all can be characterized by a direction of propagation and a speed of propagation, though the speeds are different for different kinds of waves.