Power factor and three-phaseQuestion 1265 of 1506

How does the power factor of an induction motor change when the shaft load goes up?

It falls, because the rotor reflects more reactive current.
It rises, because the rotor reflects more resistance.
It stays the same, because the stator voltage is fixed.
It turns leading, because the rotor draws more current.

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Correct answer: It rises, because the rotor reflects more resistance.

Load adds real current, so the power factor rises toward its full-load value.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 13.7: Tesla Polyphase Induction Motors

Questions last reviewed: 18 October 2026

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