Red Seal Electrician Practice
AC theoryQuestion 934 of 1506

What does Lenz’s Law say about the voltage induced in an inductor?

  1. Its polarity always helps any change in the current
  2. It opposes any change in current
  3. It is zero in all AC circuits at 60 Hz
  4. It is always the same as the supply polarity
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Correct answer: It opposes any change in current

The induced voltage pushes against an increase in current and pushes with the current when it decreases.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 3.2: AC Inductor Circuits

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Questions last reviewed: 18 October 2026