Trough:

Define: A trough is the negative part of the wave. It is the lowest point of the wave. Below the peak and the equilibrium. A trough for example is like the valley between mountains and the mountain tops are the peak, if you can imagine what I'm saying. The Amplitude is the transition of from peak to equlibrium to trough and in reverse.

Unlike amplitude, trough is..... The trough is only the lowest point of the wave and the amplitude is the oscillation of a wave.

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