A transformer is used to light 140 W, 24 V lamp from a 240 V ac mains. If the main…
Physics · Class 12 · CBSE — Alternating Current
A transformer is used to light 140 W, 24 V lamp from a 240 V ac mains. If the main current is 0.7 A, the efficiency of the transformer is
- 63.8%
- 74%
- 83.3%
- 48%
Answer
(C) 83.3%
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