A capacitor is connected to the terminals of a variable frequency oscillator. The peak voltage of the source is kept fixed while the frequency is increased. Which statement is true?
A) The rms current through the capacitor decreases.
B) The rms current through the capacitor increases.
C) The phase angle between the current and source voltage changes.
D) The current becomes zero when the frequency is large enough.

Question

Quizplus · Accepted Answer

The current through a capacitor in an AC circuit is given by I = 2πfC V, where f is the frequency, C is the capacitance, and V is the peak voltage. As the frequency is increased, the current increases proportionally. The rms current is given by Irms = I/√2, which means that the rms current also increases with frequency. Therefore, option B is correct. Options A, C, and D are not necessarily true in this scenario.

A Capacitor Is Connected to the Terminals of a Variable