CBSE Class 11-science Answered

Waves created in water can be transverse or longitudinal. For example if a stone is dropped in a pond, the waves that spread out from the source of disturbance are transverse waves.

However, longitudinal waves can also be created in water. For example if it is enclosed in a tube witha rigid wall at the right end and a movable piston at the left end. If we give the piston a single back and forth motion, displacement and pressure variations travel down the length of the medium. This is a longitudinal wave.