Which statement is true about AC induction motors?

Which statement is true about AC induction motors?

• A. They are powered by DC
• B. They require frequent brush replacement
• C. They do not have brushes or armature
• D. They have carbon brushes

Answer: (C)

AC induction motors use a rotating magnetic field created by the stator windings fed with alternating current, and the rotor carries currents induced by that field. Because the rotor isn’t connected to the power supply, there’s no commutator and no brushes, and the rotor isn’t an armature in the DC-machine sense. That’s why the true statement is that they do not have brushes or armature. They’re powered by AC, not DC, and they don’t require brush replacement or carbon brushes.

AC induction motors use a rotating magnetic field created by the stator windings fed with alternating current, and the rotor carries currents induced by that field. Because the rotor isn’t connected to the power supply, there’s no commutator and no brushes, and the rotor isn’t an armature in the DC-machine sense. That’s why the true statement is that they do not have brushes or armature. They’re powered by AC, not DC, and they don’t require brush replacement or carbon brushes.