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An observer moves towards a stationary source of sound, with a velocity one fifth of the velocity of sound. What is the percentage increase in the apparent frequency?

Options

  1. Azero
  2. B0.5 %
  3. C5 %
  4. D20 %

Correct answer

D. 20 %

Step-by-step solution

f= v+v / 5 v f= 6 f 5 % increase in frequency =20 %

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