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Two sitar strings, A and B playing the note ' D h a ' are slightly out of tune and produce beats of frequency 5 Hz . The tension of the string B is slightly increased and the beat frequency is found to decrease by 3 Hz . If the frequency of A is 425 Hz . The original frequency of B is

Options

  1. A428   Hz
  2. B430   Hz
  3. C422   Hz
  4. D420   Hz

Correct answer

D. 420   Hz

Step-by-step solution

The frequency of B is either 420   Hz or 430 Hz. As, the tension in B is increased its frequency will increase. If the frequency is 430   Hz , the beat frequency will increase. If the frequency is 420   Hz beat frequency will decrease, hence the correct answer is 420   Hz .

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