Efficiency n=90
⇒0.9×powerin=Powerout
0.9×2300×5=230×Iout
Iout=45A
JEE Main 2019 — Physics Electromagnetism
A power transmission line feeds input power at 2300V to a step down transformer with its primary windings having 4000 turns. The output power is delivered at 230V by the transformer. If the current in the primary of the transformer is 5A and its efficiency is 90, the output current would be:
Held on 9 Jan 2019 · Verified 6 Jul 2026.
35A
25A
50A
45A
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