Red Seal Electrician Practice
MotorsQuestion 1291 of 1506

A single-phase induction motor has only one stator coil and its rotor is stopped. What does the coil give?

  1. A rotating field with full starting torque
  2. A pulsating field that gives no starting torque
  3. A constant DC field
  4. A field that rotates at half speed
Show answer

Correct answer: A pulsating field that gives no starting torque

The two counter-rotating fields cancel at standstill, so the rotor does not start.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 13.9: Single-phase Induction Motors

Practice motors

Questions last reviewed: 18 October 2026