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A man is watching two trains, one leavin...

A man is watching two trains, one leaving and the other coming in with equal speeds of `4 m//s`. If they sound their whistles, each of frequency 240 Hz, the number of beats heard by the man (velocity of sound in air = `320 m//s`) will be equal to

A

6

B

3

C

0

D

12

Text Solution

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The correct Answer is:
A
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