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Two factories are sounding their sirens ...

Two factories are sounding their sirens at 800 Hz. A man goes from one factory to the other at a speed of 2 m/s. The velocity of sound is 320 m/s. The number of beats heard by the person is 1 s will be

A

2

B

8

C

4

D

10

Text Solution

Verified by Experts

The correct Answer is:
D
`n_(1)^(2) = n [(v + v_(0))/(v)] = 805`
`n_(2)^(1) = n[(v - v_(0))/(v)] = 795`
`n_(1)^(1) - n_(2)^(1) = 10`
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