Question

an echo returned in 3 s .what is the distance of the reflecting surface from the source given that speed of sound is 342 ms^-1 ? please explain completly.​

Answer 1

Solution :-

As per the given data ,

• Time taken by the echo to return (t)= 3 s

• Speed of the sound (v) = 342 m /s

we know that ,

⟹ v = d / t

on rearranging ,

⟹ D= v x t

⟹ D = 342 x 3

⟹ D = 1026 m

Distance covered by the sound to travel from source to reflecting surface = Distance covered by the sound to travel from  reflecting surface back to the source

⟹ D = d + d

⟹ D = 2d

⟹ d = D / 2

⟹ d = 1026 /2

⟹ d = 513 m

The distance of the reflecting surface from the source is 513 m

Answer 2

Answer:

Given,

Speed of sound,

$v = 342ms ^{ - 1}$

Time taken for hearing the echo, t = 3 s

Distance travelled by the sound wave

$= v \times t \\ = 342 \times 3 \\ = 1026m$

In the given time interval i.e. in 3 second, sound has to travel a distance that is twice the distance of the reflecting surface and the source.

Hence, the distance of the reflecting surface from the source is

$d = 1026 \div 2 \\ = 513m$

Hope it's helpful