A graph of displacement against distance for a wave passing through water is given below.

Wave diagram
  1. What is the wavelength of the wave?
  2. What is the amplitude of the wave?
Wave graph showing wavelength

Wavelength is the distance covered by a full cycle of the wave, usually measured from peak to peak, or trough to trough. The distance between 2 peaks is 8 m. The wavelength of the wave is 8 m.

Wave graph showing the amplitude of a wave

Amplitude is the maximum displacement of a point of a wave from its rest position.

The maximum displacement is 2.5 mm.

The amplitude of the wave is 2.5 mm.

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