MCQ
A capacitor becomes a perfect insulator for:
- AAlternating current
- ✓Direct current
- CBoth $(a)$ and $(b)$
- DNone of these
✓
Answer
Correct option: B.
Direct current
A capacitor becomes a perfect insulator for direct current as the regular supply of current charges capacitor and the it behaves as open circuit, where as in $A.C.$ the current being variable in sign and magnitude does not charge capacitor ever it goes through a repetitive process of charging and discharging and hence it never behaves as open circuit.
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