In three-phase induction motors sometimes copper bars are placed deep in the rotor to___________?
Correct answer: A. improve starting torque
- A. improve starting torque
- B. reduce copper losses
- C. improve efficiency
- D. improve power factor
Explanation
Deep rotor bars produce a strong skin effect during starting, increasing the effective rotor resistance. Since starting torque improves with suitable rotor resistance, the motor develops better starting torque.
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