ABSTRACT
This chapter considers what a sound wave is, how it is propagated, and what the rules are those govern its behavior. From a physical viewpoint, sound is a mechanical disturbance that is propagated through an elastic medium. This physical disturbance alters certain properties of the medium, and the rapid variation of one of them, for example, the variation of pressure as a function of time, might be called the sound wave. A sound wave is a relatively rapid change in pressure. It should be clear from the molecular considerations that this rapid change in pressure can travel over some distance. The ideal communication wave must move over distance so that the form of f is preserved. The movement of a real sound wave depends on the interaction of the molecules of the gas when a disturbance occurs. The chapter details the sound waves that is extremely important in acoustic analysis—sinusoidal waves.
