What is the rotor in an electric motor?

• A. The stationary part that generates the magnetic field
• B. A device that stores energy
• C. Rotating part, responds to the stator's magnetic field
• D. A device that provides lubrication

Answer: (C)

In an electric motor, the rotor is the rotating part inside the machine that turns in response to the stator’s magnetic field. The stator stays stationary and creates a magnetic field (either with windings or permanent magnets). This magnetic field interacts with the rotor, producing torque that makes the rotor spin and drive the shaft. The rotor is not the stationary part that generates the field, not a device for storing energy, and not something used for lubrication. The idea is that the rotor is the moving element that converts the magnetic interaction into mechanical rotation.