MotorsQuestion 1242 of 1506

Compared with true synchronous motors, brushless DC motors tend to be

multi-kilowatt, with electromagnet rotors.
large, with squirrel cage rotors and brushes.
single speed, tied to the line frequency.
small, with permanent magnet rotors.

Show answer

Correct answer: small, with permanent magnet rotors.

Synchronous motors are usually large with electromagnet rotors.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 13.6: Brushless DC Motor

Questions last reviewed: 18 October 2026

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