Power factor and three-phaseQuestion 1169 of 1506

An oscilloscope shows that the current lags the voltage by about 37 degrees. What is the power factor?

0.8
0.6
0.37
1.0

Show answer

Correct answer: 0.8

The power factor is the cosine of the phase shift. cos 37 degrees is about 0.8.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 11.4: Practical Power Factor Correction

Questions last reviewed: 18 October 2026

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