MCQ
A capacitor is a perfect insulator for
  • A
    Alternating currents
  • Direct currents
  • C
    Both $ac$ and $dc$
  • D
    None of these

Answer

Correct option: B.
Direct currents
b
(b)  ${X_C} = \frac{1}{{\omega C}} = \frac{1}{{2\pi \nu \,C}}$; For $dc$ $\nu = 0,\,\,\,\therefore \,\,{X_C} = \infty $

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