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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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To solve the problem, we will use the Doppler effect formula for sound. The formula for the apparent frequency when the source is moving away from a stationary observer is given by: \[ f' = f \frac{v}{v + v_s} \] Where: - \( f' \) = apparent frequency (260 Hz) ...
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A railroad train is travelling at 30 m/s in still air. The frequency of the note emitted by locomotive whistle is 500 Hz. What is the frequency of the sound waves heard by a stationary listener (a) in front of the train and (b) behind the train? (speed of sound is 345m/s.)

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