15. list and define the characteristics of a wave. you should have 4 complete content related sentences (one for each part of the wave). (ref: 136-137).

The characteristics of wave are amplitude, speed , frequency and wavelength.

Explanation:

Amplitude is defined as the distance covered by the particles or molecules moving in a wave nature. So the maximum positive and negative peak position is termed as amplitude of the wave.

Every wave forms a series of crests and trough regions. The crest region is the positive amplitude while the trough region is the negative amplitude. The distance between two successive crests and troughs are termed as wavelength.

A single crest and trough forms a complete cycle. So the number of times a cycle is repeated for a given time is known as frequency. Speed is defined as the product of frequency and wavelength of the wave. In other words, speed of a wave is the rate at which the particles are moving a given area per unit time.

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