MCQ
The magnetic field energy in an inductor changes from maximum value to minimum value in 5.0ms when connected to an AC source. The frequency of the source:
  • A
    20Hz.
  • 50Hz.
  • C
    200Hz.
  • D
    500Hz.

Answer

Correct option: B.
50Hz.
Frequency of the source is remain constant = 50Hz.

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