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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 speed 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 is `320(m)/(s)`) will be equal to

A

12

B

zero

C

6

D

3

Text Solution

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The correct Answer is:
C
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