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A person going away from a factory on his scooter at a speed of 36 km/hr listens to the siren of the factory. If the actual frequency of the siren is 700 Hz and a wind is blowing along the direction of the scooter at 36 km//hr, find the observed frequency heard by the person. (Given speed of sound `= 340 m//s`)

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The correct Answer is:
`680 Hz`
`f_("observer")=f_(0)((v+v_(w)-v_(0))/(v+v_(w)))=700((340+10-10)/(340+10))`
`=680Hz`
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ALLEN -WAVES AND OSCILLATIONS-Part-1(Exercise-04)[A]
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