If residual magnetism is present in a D.C. generator, the induced e.m.f. at zero speed will be____________?
Correct answer: A. zero
- A. zero
- B. small
- C. the same as rated voltage
- D. high
Explanation
Residual magnetism can provide flux, but generated emf also depends on speed, as given by E = kΦN. At zero speed, the induced emf is therefore zero.
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