Question

A capacitor becomes a perfect insulator for

• A. alternating current
• B. direct current
• C. both (a) and (b)
• D. None of these

Answer 1

The correct option is 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.