Red Seal Electrician Practice
AC theoryQuestion 908 of 1506

On a sine wave, where is the voltage changing most quickly?

  1. At the positive peak
  2. At the negative peak
  3. It changes at the same rate everywhere
  4. At the zero crossing
Show answer

Correct answer: At the zero crossing

The curve is steepest where it crosses zero, and flattest at the peaks.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 1.2: AC Waveforms

Practice ac theory

Questions last reviewed: 18 October 2026