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A car with a horn of frequency 620 Hz, t...

A car with a horn of frequency 620 Hz, travels towards a large wall with a speed `20ms^-1`. If velocity of sound is `330ms^-1` the frequency of echo of sound of horn as heard by driver

A

700 Hz

B

660 Hz

C

620 Hz

D

550 Hz

Text Solution

Verified by Experts

The correct Answer is:
A
Apparent frequency `n'=nxx(v+v_0)/(v-v_s)`
`n'=620((330+20)/(330-20))`
`n'=620xx350/310`
`n'=700Hz`
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