A capacitor is a perfect insulator for:
Correct answer: A. Direct current
- A. Direct current
- B. Alternating current
- C. Both (a) and (b)
- D. None of above
Explanation
A capacitor is a perfect insulator for direct current (DC) because it blocks the flow of DC through it. However, for alternating current (AC), a capacitor allows the flow of current, as it charges and discharges with the changing voltage.
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About Alternating Current
Alternating current varies periodically, so phase relationships become essential when current passes through a resistor, capacitor or inductor. The chapter distinguishes resistance from capacitive and inductive reactance, explains phase lead and lag, and connects changing electric and magnetic fields with the production and properties of electromagnetic waves.
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