For a transformer, operating at constant load current, maximum efficiency will occur at______________?
Correct answer: D. unity power factor
- A. 0.8 leading power factor
- B. 0.8 lagging power factor
- C. zero power factor
- D. unity power factor
Explanation
With load current fixed, transformer losses are essentially fixed, while useful output is proportional to power factor. The output and hence efficiency are greatest at unity power factor.
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