In a purely capacitive AC circuit, the current
Correct answer: B. leads the voltage by 90 degrees
- A. lags the voltage by 90 degrees
- B. leads the voltage by 90 degrees
- C. is in phase with the voltage
- D. is zero
Explanation
A capacitor must charge before a voltage can appear across it, so the current is greatest when the voltage is momentarily zero and falls to zero when the voltage is at its peak, putting the current a quarter cycle ahead. The mnemonic ICE captures this: in a capacitor, I comes before E. An inductor does the reverse, with the current lagging.
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About AC Through Resistor, Capacitor and Inductor
Alternating current through a resistor, capacitor and inductor involves phase relationships between voltage and current, reactance, impedance and energy transfer. A resistor keeps voltage and current in phase, while a capacitor and inductor produce opposite phase shifts, a distinction used in circuit diagrams and numerical calculations.
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592 free Alternating Current MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
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