(i) The sea water gets pushed up & down because of the wind. The raised up portion of the wave is called crest & the depressed one is called trough.
(ii) The vertical distance between a crest and the following trough is called the amplitude of the wave whereas the distance between two successive crests or troughs is called wave length.
(iii) The wave length, its amplitude & its velocity depend on the velocity of the wind.
