When the crest of one wave passes through another wave what occurs?

Answer 1

When the crest, or high point, of one wave passes through the crest of another wave, both of the crests' heights are added into one larger crest. After they pass, each crest becomes its original height that they were before the incident. This phenomena called constructive interference. This also occurs when the trough, or low point, of a wave passes through the trough of another. Now, when the crest of one wave passes through the trough of another, the height and depth of each is added (think of the trough's depth as a negative number) and the resulting amplitude (the distance from the middle of the wave) is "constructed". And once again, after the crest and trough finish passing each other, both crest and trough become their original amplitude that they were before the incident. This phenomena is called destructive interference.