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NEST2018PhysicsWaves and Sound

A source of sound emitting at a frequency f is moving towards a wall with speed v_ b . If v is the speed of sound then the beat frequency heard by a stationary observer behind the source is

Options

  1. Av_ b v-v_ b f
  2. Bv_ b v+v_ b f
  3. C2 v_ b v v^2-v_ b ^2 f
  4. D2 v_ b ^2 v^2-v_ b ^2 f

Correct answer

C. 2 v_ b v v^2-v_ b ^2 f

Step-by-step solution

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