What term describes the total opposition to the flow of current in an AC circuit?

The term that describes the total opposition to the flow of current in an AC circuit is impedance. Impedance encompasses not just resistance, which is the opposition to current flow that dissipates energy as heat, but also includes reactance. Reactance accounts for the opposition due to the circuit's inductive and capacitive components, which can store energy as electric and magnetic fields.

When dealing with alternating current (AC), the behavior of the circuit components can be quite different from that in a direct current (DC) circuit due to the phase shifts introduced by both inductance and capacitance. Impedance combines these effects into a single measurement, usually expressed in ohms, allowing engineers and electricians to effectively analyze and design AC circuits.

In summary, the comprehensive nature of impedance makes it the correct term for describing the total opposition to current flow in an AC circuit, as it fully integrates both the resistive and reactive components influencing the behavior of electrical systems in various frequencies.