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A sound wave has frequency of 2 kHz and wavelength of 35 cm . If an observer is 1.4 km away from the source, after what time interval could the observer hear the sound?

Options

  1. A2 s
  2. B20 s
  3. C0.5 s
  4. D4 s

Correct answer

A. 2 s

Step-by-step solution

Speed of sound wave aligned v & =v & =2 10^3 35 10⁻² & =700 ~m / sec aligned Required time interval t= 1.4 10^3 700 =2 sec

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