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MHT CET202411 May 2024Morning ShiftPhysicsWaves and SoundActual

With what velocity an observer should move relative to a stationary source so that a sound of triple the frequency of source is heard by an observer?

Options

  1. ASame as velocity of sound towards the source.
  2. BSame as velocity of sound away from the source.
  3. CHalf the velocity of sound towards the source.
  4. DTwice the velocity of sound towards the source.

Correct answer

D. Twice the velocity of sound towards the source.

Step-by-step solution

Applying Doppler's effect to sound waves, we can write, n^ =n ( v+v₀ v )=n (1+ v₀ v ) . array ll & n ^ =3 n . (given) & 3 n=n (1+ v₀ v ) & 3=1+ v₀ v & v₀ v =2 v₀=2 v array

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