What is the formula for capacitive reactance, XC?

Capacitive reactance, denoted as (X_C), is a measure of how much a capacitor opposes the flow of alternating current (AC) in a circuit. The formula for capacitive reactance is derived from the relationship between the capacitance (C) of the capacitor and the angular frequency (\omega) of the AC signal.

The correct formula is given by:

[ X_C = -\frac{1}{\omega C} ]

This indicates that the capacitive reactance is inversely proportional to both the frequency of the AC signal and the capacitance. In this context, the negative sign emphasizes that capacitive reactance represents a phase shift of -90 degrees, meaning the current leads the voltage across the capacitor. Thus, as the frequency increases or the capacitance increases, the reactance decreases, allowing more AC current to flow through the capacitor.

The other options describe incorrect or unrelated relationships. For example, while (\omega C) does relate to capacitors in terms of how they can affect voltage and current in circuits, it does not represent the correct formula for capacitive reactance. Similarly, (1/\omega C) lacks the necessary negative sign, and (\omega