When a D.C. series motor is connected to A.C. supply, the power factor will be low because of____________?
Correct answer: A. high inductance of field and armature circuits
- A. high inductance of field and armature circuits
- B. induced current in rotor due to variations of flux
- C. fine copper wire winding
- D. none of the above
Explanation
When a DC series motor operates on AC, its field and armature windings have substantial inductive reactance, causing a large lagging current and low power factor. The induced rotor currents are not the principal reason stated here.
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