Question

Sound waves are

(a) transverse waves characterized by the displacement of

air molecules.

(b) longitudinal waves characterized by the displacement

of air molecules.

(c) longitudinal waves characterized by pressure

differences.

(d) Both (b) and (c).

(e) (a), (b), and (c).

Short answer

The correct option is (d).

Step-by-step solution

Understanding sound waves

A sound wave is a mechanical wave that results from the back and forth vibration of the particles of the medium, through which the sound wave is moving. Sound waves are longitudinal waves that travel through a medium like air or water.

Detailed Explanation

Sound waves are longitudinal waves, so (a) is incorrect. The sound waves can be characterized either by the longitudinal displacement of the air molecules or by the pressure differences that cause the displacements.

Hence, the correct option is (d).