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A person is standing on a railway platfo...

A person is standing on a railway platform. An engine blowing a whistle of frequency 640 Hz approaches him with a speed of `72 km//hr`. The frequency of the note heard by the person is (velocity of sound is `340 m//s`)

A

650 Hz

B

660 Hz

C

675 Hz

D

680 Hz

Text Solution

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The correct Answer is:
A
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