Power factor and three-phaseQuestion 1161 of 1506

A single-phase 240 V load draws 4.8 kW at a power factor of 0.8 lagging. What is the line current?

25 A
20 A
16 A
30 A

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Correct answer: 25 A

I = P / (V x PF) = 4800 W / (240 V x 0.8) = 25 A. At a power factor of 1 it would be 20 A.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 11.3: Calculating Power Factor

Questions last reviewed: 18 October 2026

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