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The amplitude of a damped oscillator decreases to 0.9 times its original magnitude in 5s. In another 10s it will decrease to α times its original magnitude, where α equals :

Options

  1. A0.729
  2. B0.6
  3. C0.7
  4. D0.81

Correct answer

A. 0.729

Step-by-step solution

A = A 0  e - bt 2 m After 5 second 0.9 A 0 = A 0  e - b 5 2 m ...... (i) After 10 more second A = A 0  e - b 1 5 2 m ...... (ii) From (i) and (ii) A = 0.729 A 0

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