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A transformer having an efficiency of 90 % is working on 200 V , 3 kW power supply. If the current in the secondary coil is 6 A , then the voltage across the secondary coil and the current in the primary coil respectively, are

Options

  1. A300   V , 15   A
  2. B450   V , 15   A
  3. C450   V , 13.5   A
  4. D600   V , 15   A

Correct answer

B. 450   V , 15   A

Step-by-step solution

Power output = 3   kW × 90 100 = 2 . 7   kW I s = 6   A ∴ V s = 2.7   kW 6   A = 450   V ⇒ I p = 3   kW 200   V = 15   A

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