At high frequency, the current through a capacitor of an alternating current circuit will be
Correct answer: B. Large
- A. Zero
- B. Large
- C. Small
- D. Varying unpredictably
Explanation
In an alternating current circuit, the current through a capacitor increases with frequency because the capacitive reactance (which opposes the flow of AC) decreases. Hence, at high frequencies, the reactance is low, allowing a large current to pass through. Option B is correct because the current becomes large as frequency increases. Option A is incorrect because the current is not zero; it's large. Option C is incorrect since the current is not small, and Option D is incorrect because the behavior is predictable with decreasing reactance.
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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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