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Two passenger trains moving with a speed...

Two passenger trains moving with a speed of `108km//hour` cross each other. One of them blows a whistle whose frequency is `750Hz`. If sound speed is `330m//s`, then passengers sitting in the other train, after trains cross each other they will hear sound whose frequency will be

A

`900Hz`

B

`625Hz`

C

`750Hz`

D

`800Hz`

Text Solution

Verified by Experts

The correct Answer is:
B

`n'=n((v-v_0)/(v+v_s))=750((330-180xx(5)/(18))/(330+108xx(5)/(18)))=625Hz`
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