ABSTRACT
This chapter explains about some of the effects that take place when a traveling wave encounters a barrier, or a different medium, or small obstacles. Such effects represent an enormous field of study, and the present account is not intended to be more than a first glimpse of the analysis of these phenomena. In discussing the connection between standing waves and traveling waves on a stretched string, the authors necessarily made some reference to the conditions that exist at the two ends of any string of limited length. They pointed out that, as a matter of experience, one can set up a standing wave by agitating one end of a string, thereby generating a traveling wave which undergoes some process of reflection at the far end. The outgoing and returning waves then conspire to produce a standing-wave pattern with nodes at fixed positions.
