Question

A direct current (DC) motor is connected to a battery by means of two leads. The motor moves for slightly lessthan half the cycle and comes to halt. Which of the following components is missing?

• A. one of the brushes
• B. commutator
• C. slip ring
• D. one of the two magnets

Answer 1

Answer: (C)

Answer is C.

Slip-ring commutator merely maintains a connection between the moving rotor and the stationary stator.
Slip rings are useful for DC motors where the current has to change direction every half revolution whereas split rings are used to make constant current connection to a commutator, which is what we want for an AC motor.
Hence, if the slip rings are not present, then the armature stops its rotation.