JEE Main 2019 Physics question
A power transmission line feeds input power at 2300 V to a step down transformer with its primary windings having 4000 turns. The output power is delivered at 230 V by the transformer. If the current in the primary of the transformer is 5 A and its efficiency is 90%, the output current would be:
Answer: (A)
Solution
Output power = 0.9 × 2300 × 5 = 10350 W; I = 10350/230 = 45 A.