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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?
Solution
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.
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