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A power transmission line feeds input power at 2300 V to a step-down transformer with its primary windings having 4000 turns giving the output power at 230 V . If the current in the primary coil of the transformer is 5 A and its efficiency is 90 % , the output current would be:

Options

  1. A45   A
  2. B50   A
  3. C20   A
  4. D25   A

Correct answer

A. 45   A

Step-by-step solution

Efficiency, η = 0.9 = P s P p V s I s = 0.9   ×   V p I p I s = 0.9   × 2300   × 5 230 = 45   A

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