The efficiencies of transformers compared with that of electric motors of the same power are____________?
Correct answer: C. much higher
- A. about the same
- B. much smaller
- C. much higher
- D. somewhat smaller
- E. none of the above
Explanation
Transformers have no rotating or mechanical losses, so their efficiencies are commonly higher than those of motors of comparable rating. Motor losses include friction, windage and mechanical bearing losses in addition to electrical losses.
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