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MHT CET202522 Apr 2025Evening ShiftPhysicsAlternating CurrentActual

An alternating e.m.f. is given by e=e₀ t . In how much time the e.m.f. will have half its maximum value, if e starts from zero ? ( T = time period, 30^ = 1 2 )

Options

  1. AT 8
  2. BT 4
  3. CT 12
  4. DT 16

Correct answer

C. T 12

Step-by-step solution

The alternating e.m.f. is characterized by e = e₀ t . For e = e₀ 2 , solving t = 1 2 yields t = 6 . Substituting = 2 T gives 2 T t = 6 , from which t = T 12 . The e.m.f. reaches half its maximum at t = T 12 from zero.

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