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Is Matter Around Us Pure

Question
CBSEENSC9006602
Wired Faculty App

An echo returned in 3 s. What is the distance of the reflecting surface from the source, given that the speed of sound is 342 ms–1?

Solution
Given,

Speed of sound, v = 342 ms-1

Time taken for hearing the echo, t = 3 s 

Distance traversed by the sound wave = vt

                                                          = 342 x 3 

                                                          =  1026 m

In 3 s, sound has to travel twice the distance between the reflecting surface and the source.

So, Distance of the reflecting surface from the source , d = 10262 = 513 m 

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Substance Dissolved

Temperature in K

283

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