Power factor and three-phaseQuestion 489 of 1506

In an AC circuit, what is the total opposition to current from resistance and reactance called?

  1. Apparent power
  2. Impedance
  3. Reactive power
  4. Conductance
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Correct answer: Impedance

Resistance and reactance combine by the Pythagorean theorem to give impedance.

Source: Trigonometry and Single Phase AC Generation for Electricians (Flinn), 1.6: Power and Impedance Triangles

Practice power factor and three-phase

Questions last reviewed: 18 October 2026