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Alternating Current question

2010 · Q149
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Alternating Current question

2010 · Q149

NEETPhysicsAlternating CurrentMCQ+4 / −1
A 220 volt input is supplied to a transformer. The output circuit draws a current of 2.0 ampere at 440 volts. If the efficiency of the transformer is 80%, the current drwn by the primary windings of the transformer is
  1. A
    3.6 ampere
  2. B
    2.8 ampere
  3. C
    2.5 ampere
  4. D
    5.0 ampere
View written solutionFree

Correct answer: D

Efficiency of the transformer,
η\eta η =

Output power
Input power



$ \Rightarrow $ $${{80} \over {100}} = {{{V_s}{I_s}} \over {{V_p}{I_p}}}$$

$ \Rightarrow $ Ip = $${{440 \times 2} \over {{{80} \over {100}} \times 220}}$$ = 5 A
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