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A whistle revolves in a circle with an a...

A whistle revolves in a circle with an angular speed of `20 rad//sec` using a string of length `50 cm`. If the frequency of sound from the whistle is `385 Hz`, then what is the minimum frequency heard by an observer which is far away from the centre in the same plane? `v=340m//s`

A

385 Hz

B

374 Hz

C

394 Hz

D

333 Hz

Text Solution

Verified by Experts

The correct Answer is:
B
`f_(min)=f_(o)((v)/(v+omegaR))=385((340)/(340+20xx0.5))=374Hz`
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