8.3 Crests and troughs (ESACM)

Waves have moving crests (or peaks) and troughs. A crest is the highest point the medium rises to and a trough is the lowest point the medium sinks to.

Crests and troughs on a transverse wave are shown in Figure 8.2.

Crests and troughs

A crest is a point on the wave where the displacement of the medium is at a maximum. A point on the wave is a trough if the displacement of the medium at that point is at a minimum.