In a D.C. generator the critical resistance can be increased by_____________?
Correct answer: C. increasing its speed
- A. increasing its field resistance
- B. decreasing its field resistance
- C. increasing its speed
- D. decreasing its speed
Explanation
Increasing speed raises the generated emf for a given field current, making the open-circuit characteristic steeper. Its intersection with the field-resistance line then permits a higher critical resistance.
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