Question

A person hears an echo of his whistle from a distant hill after 10 s. The velocity of the sound is 346 m/s. What is the distance of the hill from the person?

Answer 1

Step 1- Given

The time taken by the echo to be heard ‘t’ = $10$ seconds.

The speed of the sound (v) is $346m/s.$ d is the distance of the hill from the person.

Step 2 - To find the distance of the hill from the person

When a sound after being reflected from a suitable reflecting surface is heard again after some time. Such a sound is called an echo.

We know that the distance covered by the sound is ‘2d’.

Distance = speed x time. So, $2d=vxt.$

By substituting the given values, we get

$$\begin{gathered} 2\times d=346\times 10 \\ \Rightarrow d=\frac{3460}{2}=1730m. \end{gathered}$$

Hence, the distance of the hill from the person is 1730 m.