gen-briefly-explain-impedance-and-reactance-and-one-common-misco-5f13

Briefly explain impedance and reactance and one common misconception about it.

# Impedance and Reactance **Impedance (Z)** is the total opposition to current flow in an AC circuit, measured in ohms (Ω). It combines resistance with reactance and is represented as a complex number: Z = R + jX. **Reactance (X)** is the opposition to current flow caused specifically by capacitors and inductors in AC circuits: - **Inductive reactance (XL)**: Increases with frequency; inductors oppose changes in current - **Capacitive reactance (XC)**: Decreases with frequency; capacitors oppose changes in voltage ## Common Misconception **"Reactance dissipates power like resistance does"** This is false. Reactance stores and releases energy rather than converting it to heat. Inductors store energy in magnetic fields, and capacitors store it in electric fields. This energy oscillates back and forth between the source and the component, resulting in **zero net power dissipation** (only reactive power). Only the resistive component of impedance actually dissipates real power as heat. This is why power calculations in AC circuits distinguish between real power (watts), reactive power (VARs), and apparent power (VA).