Many small single-phase motors change speed by varying the amount of voltage applied to the motor. This method changes the speed of the rotating magnetic field of the motor.

Question

Quizplus · Accepted Answer

The speed of a single-phase motor is primarily determined by the frequency of the supply voltage, not by varying the amount of voltage. Changing the voltage mainly affects the torque and power output, not the speed.

Many Small Single-Phase Motors Change Speed by Varying the Amount