Question

Which describes a sound wave?1) A sound wave travels in a vacuum.2) A sound wave is a longitudinal wave.3) A sound wave is an electromagnetic wave.4) A sound wave has one constant speed

Answer 1

A sound wave is a longitudinal wave, i.e., the matter in the medium vibrates parallel to the direction of the propagation of the wave.

The sound wave requires a medium to travel through. Thus, it can not travel in a vacuum.

The speed of the sound wave depends on the medium in which it travels.

Thus the correct answer is option 2.