Question

A person hears the echo of his own voice from a distant hill after 2 seconds. How far away is the person from the hill, if the speed of sound is 330m/s ? ​

Answer 1

Answer: 330 m

Explanation:

The speed of sound $V$ is defined as the distance traveled by the sound wave $d$ in a especific time $t$:  

$V=\frac{d}{t}$  

Where:  

$V=330 m/s$ is the speed of sound  

$t=\frac{2 s}{2}=1 s$ is half the time the sound wave travels since the person speaks, the sound wave hits the hill and then returns to the person again  as an echo

$d$ is the distance between the person and the hill

So, we have to find $d$:

$d=Vt$

$d=(330 m/s)(1 s)$

Finally:

$d=330 m$