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3 years ago

A boy yells in a narrow valley. The sound reflects off of a boulder that is 80 m away. How long will it take to hear the echo if

Physics

2 answers:

soldier1979 [14.2K]3 years ago

4 0

Answer:4 lubeconds (speed=distance over time)

Dima020 [189]3 years ago

3 0

Answer:

Time taken, t = 0.5 seconds

Explanation:

It is given that,

Speed of sound wave, v = 320 m/s

The sound reflects off of a boulder that is 80 m away.

Let t is the time taken to hear the echo. The distance covered by the sound to hear the echo is, 2d. So,

$v=\dfrac{2d}{t}$

$t=\dfrac{2d}{v}$

$t=\dfrac{2\times 80\ m}{320\ m/s}$

t = 0.5 seconds

So, the time taken to hear the echo is 0.5 seconds. Hence, this is the required solution.

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