What is capacitive reactance?

Capacitive reactance is defined as the opposition to alternating current (AC) caused by the presence of a capacitor in a circuit. It arises from the capacitor's ability to store energy in an electric field and then release that energy, which leads to a phase difference between voltage and current. The formula for capacitive reactance (Xc) is given by (X_c = \frac{1}{2\pi f C}), where (f) is the frequency of the AC signal and (C) is the capacitance. This relationship indicates that capacitive reactance decreases as frequency increases, meaning that capacitors allow higher frequency signals to pass more easily while blocking lower frequency ones.

This understanding of capacitive reactance is vital in the analysis and design of AC circuits, where capacitors are often used for filtering, coupling, and decoupling applications. The other options provided do not define capacitive reactance correctly; they pertain to different aspects of electrical circuits, such as direct current resistance, voltage drop, and inductive loads, which are not related to how capacitors behave in AC circuits.