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A man sitting on a swing which is moving...

A man sitting on a swing which is moving to an angle of `60^(@)` from the vertical is blowing a whistle which has frequency of `2.0` KHZ. The whistle is `2.0` m from the fixed support point of the swing. A sound detector which detects the whistle sound is kept in front of the swing. The maximum frequency the sound detector detected is :

A

`2.027 kHz`

B

`1.974 kHz`

C

`9.74 kHz`

D

`1.011 kHz`

Text Solution

Verified by Experts

The correct Answer is:
A
Frequency `v= 2 kHz`
Velocity of whistle (source) `v_(s)=2m`
Velocity of sound `v=332m/s`
Maximum frequency `v_("max")=((V+V_(s))/(V))v`
`=((332+2)/(332))xx2`
`=((334)/(332)xx2`
`1.006xx2`
`2.012 kHz`
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