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Alternating Current question

2007 · Q116
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Alternating Current question

2007 · Q116

NEETPhysicsAlternating CurrentMCQ+4 / −1
A transformer is used to light a 100 W and 110 V lamp from a 220 V mains. If the main current is 0.5 amp, the efficiency of the transformer is approximately
  1. A
    50%
  2. B
    90%
  3. C
    10%
  4. D
    30%
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