Discuss how ripples are formed in still water.

Explanation

A stone is dropped in a trough of still water, we can see a disturbance produced at the place where the stone strikes the water surface is seen. The disturbance spreads out (diverges out) in the formof concentric circles of ever increasing radii (ripples) and strike the boundary of the trough. This is because some of the kinetic energy of the stone is transmitted to the water molecules on the surface. Actually the particles of the water (medium) themselves do not move outward with the disturbance. This can-be observed by keeping a paper strip on the water surface. The strip moves up and down when the disturbance (wave) passes on the water surface. This shows that the water molecules only undergo vibratory motion about their mean positions.