Efficiency, η=0.9=PpPs
VsIs=0.9×VpIp
Is=2300.9×2300×5=45A
JEE Main 2018 — Physics Electromagnetism
A power transmission line feeds input power at2300V to a step-down transformer with its primary windings having 4000turns giving the output power at 230V. If the current in the primary coil of the transformer is 5A and its efficiency is 90, the output current would be:
Held on 16 Apr 2018 · Verified 6 Jul 2026.
45A
50A
20A
25A
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