Red Seal Electrician Practice
TransformersQuestion 1081 of 1506

In an ideal transformer, what is the induced secondary voltage with an open circuit when both coils have the same turns?

  1. Zero
  2. Twice the primary voltage
  3. Equal to the primary voltage and in phase
  4. 90 degrees out of phase with the primary voltage
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Correct answer: Equal to the primary voltage and in phase

Both coils see the same flux change.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 10.1: Mutual Inductance and Basic Operation

Practice transformers

Questions last reviewed: 18 October 2026