What does capacitive reactance refer to?

Capacitive reactance refers to the opposition that a capacitor presents to the flow of alternating current (AC), which is a fundamental concept in electrical circuits, especially in AC circuits. This reactance is specifically due to the ability of capacitors to store and release electrical energy.

When AC voltage is applied across a capacitor, it causes charge to build up on the capacitor plates, which creates an electric field. This buildup of charge leads to a phase difference between the voltage across the capacitor and the current flowing through it, effectively causing the capacitor to 'react' against the changes in current. The reactance is frequency-dependent; the higher the frequency of the AC signal, the lower the capacitive reactance.

This understanding of capacitive reactance is crucial for designing and analyzing electrical systems, especially those involving filters, timing circuits, and other applications where capacitors play a significant role in determining the behavior of the circuit.

The other options describe different electrical concepts not related to capacitive reactance; one addresses resistance, another discusses electrical power loss, and the last refers to the behavior of inductors. All of these concepts are important in electrical theory, yet they do not pertain to the specific definition of capacitive reactance.