What does impedance (Z, in ohms) include?

Impedance, represented by Z and measured in ohms, is a comprehensive measure of opposition to alternating current (AC) in a circuit. It encompasses not just resistance, which is the opposition to current flow in a direct manner, but also reactance, which includes both capacitive and inductive reactance.

Capacitive reactance is the opposition to the change in voltage across a capacitor, while inductive reactance is the opposition to the change in current through an inductor. By combining resistance with the reactance from both capacitors and inductors, impedance provides a complete view of how an AC circuit will respond under various conditions.

Therefore, saying that impedance includes resistance, capacitive reactance, and inductive reactance accurately captures the full range of components that contribute to the total opposition encountered by AC signals. This understanding is crucial for analyzing and designing circuits that operate under AC conditions, allowing for predictions about circuit behavior and performance.