Question

The minimum distance between the man and the reflecting surface so that he can hear the echo is (velocity of sound 340ms)

Answer 1

Hello!!

The minimum distance between the man and the reflecting surface so that he can hear the echo is 17m.

Hope it helps ya

Answer 2

Answer:

The minimum distance between the man and the reflecting surface so that he can hear the echo is (velocity of sound 340ms) 17.2 meters.

Explanation:

• When a sound wave travels in a medium and get reflected back from the reflecting surface, we hear an echo. The sound wave must travel a minimum distance so that we can hear an echo.

• Considering the speed of sound in air as 340m/s.
• Let the distance between the source of sound and the obstacle = x m
• Thus the distance travelled by sound to reach back to the source      

                                                  $d=2\times\mathram x$

Let the minimum time required to hear an echo= 0.1sec

Velocity of sound in air v=340m/s

$Total distance d =v x t$

                      $2x=340\times0.1$

                           $=17.2 m( as calculation)$

The minimum distance between the man and the reflecting surface so that he can hear the echo is (velocity of sound 340ms) 17.2 meters.