What should be the velocity of a sound source moving towards a stationary observer so that apparent frequency is double the actual frequency (Velocity of sound is $v$)
A$v$
B$2v$
C$\frac{v}{2}$
D$\frac{v}{4}$
Medium
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C$\frac{v}{2}$
c (c) By using $n' = \left( {\frac{v}{{v - {v_S}}}} \right) $
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