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NEET2007PhysicsAlternating CurrentActual

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.

Options

  1. A50 %
  2. B90 %
  3. C10 %
  4. D30 %

Correct answer

B. 90 %

Step-by-step solution

The efficiency of transformer aligned & = V_s I_s V_p I_p 100 & = 100 220 0.5 100=90 % aligned

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