What is the total opposition to current flow in an alternating current circuit called?

The term used to describe the total opposition to current flow in an alternating current (AC) circuit is impedance. Impedance encompasses not only the resistance, which opposes current flow, but also takes into consideration the effects of capacitive and inductive components in the circuit.

In an AC circuit, the current and voltage are sinusoidal and can vary over time. This variation means that both capacitance and inductance play roles in how the circuit behaves. Capacitance opposes changes in voltage, causing a phase shift that affects current flow, while inductance opposes changes in current, also resulting in a phase shift.

Thus, impedance is a comprehensive measure that includes resistance (the opposition to current flow due to resistive elements) as well as the reactances (the opposition due to capacitive and inductive elements). Represented in complex form, impedance can be calculated by combining these different components, allowing for a clearer understanding of how AC circuits function under different conditions.