Physics

Problem

A swimmer underwater is 120\,m in front of a vertical pool wall. If the speed of sound in water is

1500\,\text{m/s}

, how much time after striking a metal plate will the swimmer hear the echo? a)

0.08\,\text{s}

0.70\,\text{s}

0.16\,\text{s}

0.32\,\text{s}