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A reflector is moving with 20 ms^(-1) to...

A reflector is moving with `20 ms^(-1)` towards a stationary source of sound. If the source is producing sound waves of 160 Hz., then the wavelen of the reflected wave is (speed of sound in air is `340 ms^(-1)`)

A

`(17)/(8)m`

B

`(17)/(11)m`

C

`(17)/(9) m`

D

`(17)/(16)m`

Text Solution

Verified by Experts

The correct Answer is:
C
Wavelength of the reflected wave is
`lamda=((v-v_(s))/(v+v_(s)))lamda =((v-v_(s))/(v+v_(s)))(v)/(v)`
`=(340-20)/(340+20)xx(340)/(160)=(120)/(360)xx(340)/(160)`
`lamda. =(17)/(9) m`
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