Power factor and three-phaseQuestion 215 of 1506

When the voltage and current of a load are out of phase, part of each cycle has negative power. What is its effect?

It is stored in the neutral conductor
It is sold back to the utility company
It flows back and heats the lines
It makes the load run a lot cooler

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Correct answer: It flows back and heats the lines

Power that flows back toward the source cannot be used, and it still heats the line conductors on the way.

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

Questions last reviewed: 18 October 2026

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