Coast Guard Exams
Question 245Electricity/Electronics - QMED70% to pass

What is the function of the commutator associated with a DC motor?

AI Explanation
The correct answer is D) allow current flow in the armature windings under a given pole to be in the same direction at all times. The commutator in a DC motor functions to maintain the direction of current flow in the armature windings as the armature rotates. This ensures that the current flow through each armature winding is always in the same direction relative to the magnetic field, which is necessary to generate a continuous rotational torque. The other options are incorrect because they do not accurately describe the primary function of the commutator. Option A is related to brush positioning, option B is about reducing magnetic reluctance, and option C is about reversing field pole polarity, none of which are the main purpose of the commutator in a DC motor.