Question

A man stands on top of a cliff and shouts.

He hears the echo on the third clap when
he claps his hand at the rate of two claps
per second. What is the distance between
man & the obstruction, if the velocity of
sound is 320 m/s

Answer 1

`\small\bf \: let \: the \: distance \: of \: the \: man \: from \: the \: cliff \: be \: x`

`\small\bf \: thus \: time \: taken \: by \: sound \: to \: hit \: the \: cilff \: and \: return = (2x)/(v) = 1`

`\bf \to \: x = (320)/(2) m = 160m`

`\small \bf \: thus \: the \: distance \: between \: the \: cliffs \: = 160m * 2 = 320m`