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MHT CET20226 Aug 2022Evening ShiftPhysicsWaves and SoundActual

A car sounding a horn of frequency 1000 ~Hz passes an observer. The ratio of frequencies of the both noted by the observer before and after passing of the car is 11:9. If the speed of sound is V , the speed of the car is

Options

  1. AV
  2. BV 10
  3. CV 100
  4. DV 5

Correct answer

B. V 10

Step-by-step solution

n_ Before = ( v v+v_c ) n And n_ After = ( v v+v_c ) n n_ Before n_ After = 11 9 = ( v+v_c v-v_c ) v_c v 10

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