question_answer 28)

                Water waves produced by a motor boat sailing in water are                 (a) neither longitudinal nor transverse.                 (b) both longitudinal and transverse.                 (c)  only longitudinal                 (d) only transverse.

Answer:

                (b) When water wave produced by the motor travel on the surface of deep water, water molecules at the surface move up and down; and back and forth simultaneously describing nearly circular paths as shown in. the surface of water has been shown in the form of crests and troughs.                                 As the wave passes, water molecules at the crests move in the direction of the wave while those at the troughs move in the opposite direction.                 Note: Waves on the surface of water are known as ripples.