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An engine standing at the platform blows...

An engine standing at the platform blows a whistle of frequency 305 vib/sec. if the velocity of sound be 1220 km/h, the frequency of the whistle as heard by a man towards the engine with a speed of 20 km/h is :

A

300 vib/s

B

305 vib/s

C

310 vib/s

D

320 vib/s

Text Solution

Verified by Experts

The correct Answer is:
C
`V. = ((V + U_(0))/(V) ) v = (1220 + 20)/(1220) . 305 = `310 Hz.
Hence the correct choicer is (c).
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