The value of power factor in pure capacitor circuit is

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Explanation: In a pure capacitor circuit, the current leads the voltage by a phase angle of $90^\circ$ (${\pi}/2$ radians). Since the power factor is defined as the cosine of this phase angle ($\cos \phi$), and $\cos(90^\circ) = 0$, the power factor of a pure capacitor is exactly 0.

Working Principle: A pure capacitor does not dissipate real power; it only stores and releases energy in the form of an electric field. Because the current waveform leads the voltage waveform by $90^\circ$, there is no component of current in phase with the voltage, leading to zero active power consumption.

Key Formulas: $P.F. = \cos(\phi)$ — Definition of Power Factor; $\phi = 90^\circ$ — Phase difference in pure capacitor

Key Points: Pure capacitive circuits are purely reactive components.; The power factor is described as 'leading' because the current leads the voltage.; Real power ($P = VI \cos \phi$) consumed by a pure capacitor is always zero.

Advantages: Used for power factor correction in industrial loads.; Improves voltage regulation in transmission lines.

Disadvantages: Cannot be found in practical circuits as they always possess some equivalent series resistance (ESR).

Applications: Capacitor banks in power systems.; Filters in electronic power supplies.

Additional Info: A pure resistor has a power factor of 1 (unity).. A pure inductor has a power factor of 0 (lagging).

Answer: A is correct — The power factor is 0 because the phase angle between voltage and current in a purely capacitive circuit is $90^\circ$, and $\cos(90^\circ) = 0$.

Exam Tip: Remember: RLC circuits have a power factor between 0 and 1; only ideal reactive elements (L or C) have a power factor of 0.

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