A sound wave of frequency travels through air at

PHYSICS · Single correct · A Level · Physics · Waves · Waves

Problem

A sound wave of frequency

425\,\text{Hz}

travels through air at

v = 340\,\text{m/s}

. In

0.02\,\text{s}

, which of the following describes the situation correctly? (a) The disturbance covers

8.5\,\text{m}

, and each air molecule moves

8.5\,\text{m}

forward permanently. (b) The disturbance covers

0.8\,\text{m}

, and each air molecule eventually returns to its original position. (c) The disturbance covers

6.8\,\text{m}

, and each air molecule eventually returns to its original position. (d) The disturbance covers

6.8\,\text{m}

, and each air molecule is displaced

6.8\,\text{m}

forward permanently.