An observer moves towards a stationary source of sound with a velocity equal to one-fifth of the velocity of sound. The percentage change in the frequency will be :
Solution
<p>$f' = {f_0}\left[ {{{v - {v_0}} \over {v - {v_s}}}} \right]$</p>
<p>$\Rightarrow f' = {f_0}\left[ {{{v + {v \over 5}} \over v}} \right]$</p>
<p>$\Rightarrow f' = {{6{f_0}} \over 5}$</p>
<p>$\Rightarrow$ % change = 20</p>
About this question
Subject: Physics · Chapter: Waves · Topic: Wave Motion and Types
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