Question

A man standing on a cliff claps his hand, and hears its echo after $1\text{s}$. If sound is reflected from another mountain and velocity of sound in air is $340\text{m/s}$, then the distance between the man and the mountain is

• A. $680\text{m}$
• B. $340\text{m}$
• C. $185\text{m}$
• D. $170\text{m}$

Answer 1

The correct option is D $170\text{m}$

Given:
$v_s=340\text{m/s}$

Time taken by sound to return to man is $1\text{s}.$

So, time taken by sound to reach the mountain is $0.5\text{s}.$

$\therefore d=v_{s}t$

$\Rightarrow d=340\times 0.5=170\text{m}$