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NEETPhysicsWaves and Sound

What is the frequency of the sound heard by an observer standing on the platform when a train, which initially emits a whistle of frequency 400 Hz in still air, starts moving towards the platform at a speed of 10 m/s? (Assume the speed of sound in air is 330 m/s)

Options

  1. A400 Hz
  2. B412.5 Hz
  3. C425 Hz
  4. D390 Hz

Correct answer

B. 412.5 Hz

Step-by-step solution

Correct Option is : (B) 412.5 Hz

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