Question

Solve the following problem.

A man standing between 2 parallel cliffs fires a gun. He hears two echoes one after 3 seconds and other after 5 seconds. The separation between the two cliffs is 1360 m, what is the speed of sound?

Answer 1

Given: distance (s) = 1360 m, t
ime for first echo = 3 s,
time for second echo = 5 s

To find: speed of sound (v)

Formula: speed = `"distance"/"time"`

Calculation: Time for first echo = 3 s

∴ time taken by sound to travel given distance t₁

=`3/2` = 1.5 s 

Time for second echo = 5 s

∴ time taken by sound to travel given distance t₂

`= 5/2` = 2.5 s

∴ Total time taken by sound to travel given distance, T = 1.5 + 2.5 = 4 s

From formula, v = `1360/4`

∴ v = 340 m/s

The speed of sound is 340 m/s.