MCQ
A capacitor becomes a perfect insulator for:
- AAlternating current
- BDirect current
- CBoth (a) and (b)
- DNone of these
✓
Answer
- Direct current
Explanation:
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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