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If a stationary observer notes a change ...

If a stationary observer notes a change of 25% in the frequency of a whistle of an engine coming towards him, then the velocity of the engine is (velocity of sound = `332 m//s`)

A

66.4 m/s

B

64 m/s

C

60 km/hr

D

32 km /hr

Text Solution

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The correct Answer is:
B
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