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MHT CET20228 Aug 2022Morning ShiftPhysicsWaves and SoundActual

The velocity of sound is 340 ~m / s . A source of sound having frequency of 90 ~Hz is moving towards a stationary observer with a speed of one-tenth that of sound. The apparent frequency of sound as heard by the observer is

Options

  1. A45 ~Hz
  2. B100 ~Hz
  3. C80 ~Hz
  4. D50 ~Hz

Correct answer

B. 100 ~Hz

Step-by-step solution

Apparent frequency of sound heard by the observer is: f=f₀ ( v v-v_s ) Where, v=340 ~m / s is the speed of sound & v_s=v / 10 is the speed of the source morning towards the observer. f=90 ( v v- v 10 ) Hz =90 ( 10 9 ) Hz =100 ~Hz

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