The commutator segments continually change polarity from positive to negative, which causes the magnetic field in the armature to change polarity form north pole to south pole.

Question

Quizplus · Accepted Answer

The commutator in a DC motor reverses the current direction through the armature windings at appropriate times as the armature rotates. This action ensures that the magnetic field created by the armature interacts with the stationary magnetic field in a manner that produces continuous rotation. The reversal of current effectively changes the polarity of the magnetic field in the armature, switching from north to south and vice versa, to maintain consistent torque direction.

The Commutator Segments Continually Change Polarity from Positive to Negative