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
6
B
3
C
4
D
8
Text Solution
Verified by Experts
The correct Answer is:
A
`f_(b)=(2V_(s))/Vxxf=6Hz`
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