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NEET UG PHYSICS MCQ: ALTERNATING CURRENT
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A transformer is used to light 140 W, 24 V lamp from 240 V AC mains. The current in the mains is 0.7 A. The efficiency of transformer is nearest to
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Correct option: B
0.8
Option B (0.8) is correct because the efficiency is the ratio of output power to input power, which is approximately 0.8.
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