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A train approaches stationary observer, ...

A train approaches stationary observer, the velocity of train being `1/20` of the velocity of sound. A sharp blast is blown with the whistle of the engine at equal intervals of 1s. The interval between the successive blasts as heard by the observer

A

`(1)/(20)`sec

B

`(1)/(20)`min

C

`(19)/(20)`sec

D

`(10)/(20)`min

Text Solution

Verified by Experts

The correct Answer is:
C
`f=(1)/(T)=(1)/(1)=1Hz`
Frequency heard by the observer
`f.=f((v)/(v-v_(s)))=1((v)/((19v)/(20)))=(20)/(19)Hz`
`t=(1)/(f.)=(19)/(20)sec`.
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