Question

Large transformers, when used for some time, become very hot and are cooled by circulating oil. The heating of the transformer is due to
A. the heating effect of current alone
B. hysteresis loss alone
C. both the heating effect of current and hysteresis loss
D. intense sunlight at noon

Answer 1

C. both the heating effect of current and hysteresis loss
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Large transformers, when used for some time, become very hot and are cooled by circulating oil. The heating of the transformer is due to both the heating effect of current and hysteresis loss.

Answer 2

C. both the heating effect of current and hysteresis loss
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Large transformers, when used for some time, become very hot and are cooled by circulating oil. The heating of the transformer is due to both the heating effect of current and hysteresis loss