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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 1 km from the hill. Wind with a speed of 40 km/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 echo from the hill is heard by the driver and its frequency. (Velocity of sound in air = 1200 km/hr)

A

599 Hz

B

590 Hz

C

610 Hz

D

620 Hz

Text Solution

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The correct Answer is:
D
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