Synchronous motors are not self starting because
- A. Stator not used
- B. Starting winding not provided
- C. There is no slip
- D. The direction of instantaneous torque on the rotor reverses after half cycle
Answer: D. The direction of instantaneous torque on the rotor reverses after half cycle
Explanation: The torque on the rotor reverses every half cycle (averages to zero) because the rotor cannot follow the rotating field from standstill.