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A police car moving at 22 m/s, chases a ...

A police car moving at 22 m/s, chases a motorcylist. The police man sounds his horn at 176 Hz, while both of them move towards a stationary siren of frequency 165 Hz. Calculate the speed of the motorcycle, if it is given that he does not observes any beats

A

33 m/s

B

22 m/s

C

zero

D

11 m/s

Text Solution

Verified by Experts

The correct Answer is:
B
The motorcyclist observes no beats, So, the apparent frequency observed by him from the two sources must be equal.
` f_(1)=f_(2):.176((330-v)/(330-22))=165((330+v)/(330))`
Solving this equation, we get `v = 22 m//s`.
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ALLEN -WAVES AND OSCILLATIONS-Part-1(Exercise-05)[B]
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