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A train approaching a hill at a speed of...

A train approaching a hill at a speed of `40 km//hr` sounds a whistle of frequency `580 Hz` when it is at a distance of `1km` from a hill. A wind with a speed of `40km//hr` is blowing in the direction of motion of the train Find
(i) the frequency of the whistle as heard by an observer on the hill,
(ii) the distance from the hill at which the echo from the hill is heard by the driver and its frequency.
(Velocity of sound in air `= 1, 200 km//hr`)

A

599 Hz

B

590 Hz

C

610 Hz

D

620 Hz

Text Solution

Verified by Experts

The correct Answer is:
D
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