Editing Crest and trough (section)

{{Short description|Feature of a transverse wave}}
{{one source |date=March 2024}}
[[Image:Crest_trough.svg|thumb|upright=1.5|Crest and trough in a wave]]
A '''crest''' point on a [[wave]] is the highest point of the wave. A crest is a point on a [[surface wave]] where the [[Particle displacement|displacement]] of the medium is at a maximum. A '''trough''' is the opposite of a crest, so the [[minimum]] or lowest point of the wave.

When the crests and troughs of two [[sine wave]]s of equal [[amplitude]] and [[frequency]] intersect or collide, while being in [[phase (waves)|phase]] with each other, the result is called ''constructive'' [[wave interference|interference]] and the magnitudes double (above and below the line). When in [[:wiktionary:antiphase|antiphase]] – 180° out of phase – the result is ''destructive'' interference: the resulting wave is the undisturbed line having zero [[amplitude]].