At a high frequency, the alternating current through a capacitor in an alternating currentcircuit will be
Correct answer: B. The current will be large.
- A. The current will be zero.
- B. The current will be large.
- C. The current will be small.
- D. The current will be undetermined.
Explanation
In an AC circuit, a capacitor's reactance decreases as the frequency increases. Therefore, at high frequencies, the capacitive reactance becomes very low, allowing a large amount of current to flow through the capacitor. This is why Option B is correct. Option A is incorrect because the current is not zero at high frequencies. Option C is incorrect because the current is not small; instead, it is large due to reduced reactance. Finally, Option D is incorrect because the behavior of a capacitor is predictable and not undetermined.
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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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