If frequency increase, IC will

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Increase

Explanation: In an A.C. circuit containing a capacitor, the capacitive reactance ($X_C$) is inversely proportional to frequency ($f$). As frequency increases, $X_C$ decreases, which leads to an increase in the capacitive current ($I_C$) according to Ohm's law ($I_C = \frac{V}{X_C}$).

Working Principle: The current flowing through a capacitor is governed by the relation $I_C = V 	imes 2\pi f C$. Because the current is directly proportional to frequency, an increase in frequency results in a higher rate of charge and discharge cycles, effectively allowing more current to pass through the dielectric medium of the capacitor.

Key Formulas: $X_C = \frac{1}{2\pi f C}$ — Capacitive Reactance; $I_C = V \cdot 2\pi f C$ — Capacitive Current

Key Points: Capacitive reactance ($X_C$) is inversely proportional to the frequency of the supply voltage.; A capacitor acts as an open circuit to D.C. ($f=0$) and as a short circuit at very high frequencies.; In A.C. parallel circuits, frequency-dependent branches determine the total admittance of the circuit.

Advantages: Used in frequency-sensitive filtering applications.; Essential for power factor correction using capacitor banks.

Disadvantages: High frequency sensitivity can lead to instability in resonant circuits.; Excessive current at high frequencies can overheat components.

Applications: High-pass filters; Coupling capacitors in amplifiers; Power factor improvement in industrial grids

Additional Info: This behavior is specific to capacitive circuits; for inductive circuits, current decreases as frequency increases because $X_L = 2\pi f L$.. The option 'Decrease' is incorrect because it describes the behavior of an inductive load.

Answer: A is correct — The capacitive current $I_C$ increases because the capacitive reactance $X_C$ decreases as the frequency increases.

Exam Tip: Always remember the mnemonic 'ELI the ICE man': In Inductors (L), E leads I; in Capacitors (C), I leads E, and remember $X_C \propto 1/f$ vs $X_L \propto f$.

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