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Manipal MET2020PhysicsWaves and Sound

If an observer moves towards stationary source, then the apparent frequency is given by

Options

  1. Af^ =f ( v+v₀ v )
  2. Bf^ =f ( v-v₀ v )
  3. Cf^ =f ( v v+v₀ )
  4. Df^ =f ( v v-v₀ )

Correct answer

A. f^ =f ( v+v₀ v )

Step-by-step solution

Generalised formula for apparent frequency is f_a= ( v v_o v v_s ) f₀ According to the question source is stationary, v_s=0f_a=f^ = ( v v₀ v ) f₀ Observer is moving towards the source f_a=f^ = ( v+v₀ v ) f where, v= speed of the wave v_o= speed of the observer f= original frequency of the source

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