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NTA Abhyas JEE Main2020PhysicsWaves and SoundPractice

Two sound waves of wavelengths 98 c m and 100 c m arrive at the same point, from two different sources. If the speed of sound in the medium is 392 m s - 1 , then the number of beats heard is

Options

  1. A8   Hz
  2. B4   Hz
  3. C6   Hz
  4. D12   Hz

Correct answer

A. 8   Hz

Step-by-step solution

The beat frequency = | f 1 - f 2 | , where f = c λ f beat = 392 0 . 98 - 392 1   Hz f beat = 8   Hz

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