A GIF Animation Wave interference is a phenomenon which occurs when two waves meet while traveling along the same medium. Wave interference can be constructive or destructive. When a crest meets a crest, the resultant displacement of the medium at that location is larger than the displacement of either of the two individual wave crests. A new and larger wave is constructed.
Destructive interference occurs wherever a crest of one wave meets a trough of a second wave.
When a crest meets a trough, the two individual waves combine to produce a new wave which has a resultant displacement which is smaller than the displacement of the larger wave. That is, the two waves combine to either partially or completely destroy each other. The interference of two sets of circular waves with the same frequency and the same amplitude results in a standing wave pattern. These standing wave patterns are known as two-point source interference patterns since they result from the interference of circular waves from two sources. A standing wave pattern is a wave pattern in which there are points along the medium which appear to be standing still.