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The frequency of the whistle of a train ...

The frequency of the whistle of a train is observed to drop from 280 Hz to 260 Hz as the train moves away from a stationary listerner on the platform. Calculate the speed of the train, if speed of sound in air is 340 m/s.

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26.15 m/s
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A train in approaching a station with a uniform velocity of 72kmph and the frequency of the whistle of that train is 480Hz . The apparent increase in the frequency of that whistle heard by a stationary observer on the platform is (Velocity of sound in air is 340m//s )

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A train moving at a speed of 220ms^-1 towards a stationary object emits a sound of frequency 1000 Hz. Some of the sound reaching the object gets reflected back to the train as echo. The frequency of the echo as detected by the driver of the train is (speed of sound in air is 330ms^(-1) )

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Two trains are moving towards each other at speeds of 72kmh^-1 and 54 kmh^-1 relative to the ground. The first train sounds a whistle of frequency 600 Hz. Find the frequency of the whistle as heard by a passenger in the second train a. before the trains meet and b. after teh trains have crossed each other. The speed of sound in air is 340 ms^-1

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