A source of sound S is moving with a velocity | vedclass

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(C) Let $f$ be the actual frequency of the source,$V = 350\,m/s$ be the velocity of sound,and $V_s = 50\,m/s$ be the velocity of the source.When the s

Vedclass · Accepted Answer

$750$

Vedclass · Answer

(C) Let $f$ be the actual frequency of the source,$V = 350\,m/s$ be the velocity of sound,and $V_s = 50\,m/s$ be the velocity of the source.When the source is moving towards the stationary observer,the apparent frequency $f_a$ is given by:$f_a = \frac{V}{V - V_s} f = 1000\,Hz$$1000 = \frac{350}{350 - 50} f = \frac{350}{300} f = \frac{7}{6} f$So,the actual frequency $f = 1000 	imes \frac{6}{7} = \frac{6000}{7}\,Hz$.When the source is moving away from the observer,the apparent frequency $f_a'$ is given by:$f_a' = \frac{V}{V + V_s} f$Substituting the values:$f_a' = \frac{350}{350 + 50} 	imes \frac{6000}{7} = \frac{350}{400} 	imes \frac{6000}{7} = \frac{7}{8} 	imes \frac{6000}{7} = \frac{6000}{8} = 750\,Hz$.

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