Tag: determination of speed of sound by echo

Questions Related to determination of speed of sound by echo

Multiple choice physics study of sound determination of speed of sound by echo problems on sound sound needs a medium

A boy shouts while standing in front of a hill. He hears an echo after 6 sec. If the speed of sound  in air is 340 m/s. What is the distance of the hill from the position of the body?

  1. 519 m

  2. 1020 m

  3. 2040 m

  4. none

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let distance of hill from the position of the body = d
Echo is heard after 6 sec
$d = v \dfrac{t}{2}$
$= \dfrac{(340 \times 6)}{2}$
$= 1020 m$

Multiple choice physics study of sound determination of speed of sound by echo problems on sound sound needs a medium

A sonar echo takes 8.8 s to return from a shack. How far away is the shack?

Given speed of sound in sea-water = 1533 m/s

  1. 348 m

  2. 5720 m

  3. 6745 m

  4. 13490 m

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let $d$ be the distance of shack from the sonar . Therefore  distance covered by sound to come back to sonar after reflection from shack ,  $=d$ ,

given , speed of sound in sea water $v=1533m/s  ,  t=8.8s$ ,
we have , distance=speed$\times time$ ,
               $d=v\times t=1533\times8.8$ ,
or            $d=13490.4m$