2.6 EM

What is the primary difference between a synchronous motor and an induction motor?

• a) Synchronous motors use brushes, while induction motors do not.

• b) Synchronous motors operate at synchronous speed, while induction motors do not.

• c) Synchronous motors have a single-phase power supply, while induction motors have a three-phase power supply.

• d) Synchronous motors require a rotor current to produce a rotating magnetic field, while induction motors do not.

Which of the following is a characteristic of a synchronous motor?

• a) High starting torque

• b) Self-starting capability

• c) Low power factor

• d) Constant speed under varying loads

How is the rotor of a synchronous motor magnetized?

• a) By applying DC voltage to the rotor windings

• b) By using permanent magnets

• c) By inducing a magnetic field from the stator windings

• d) By applying AC voltage to the rotor windings

What is the function of damper windings in a synchronous motor?

• a) To provide starting torque

• b) To regulate the output voltage

• c) To dampen vibrations and stabilize rotor motion

• d) To provide cooling for the motor

5. In a synchronous motor, the stator winding produces a rotating magnetic field that interacts with the rotor. Which type of current is used to create this magnetic field?

• 5. a) DC current

• 5. b) Single-phase AC current

• 5. c) Three-phase AC current

• 5. d) Pulsating current