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Alternating Current

JEE Main level, single correct, medium

184 of 190

Question 184 of 190

A power transmission line feeds input power at $2300V$ to a step-down transformer with its primary windings having $4000$ turns 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:

Show answer and solution

Answer: (A) $45A$

Efficiency,

\eta =0.9=\dfrac{{P}_{s}}{{P}_{p}}

{V}_{s}{I}_{s}=0.9\times {V}_{p}{I}_{p}

{I}_{s}=\dfrac{0.9\times 2300\times 5}{230}=45A

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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JEE Main Physics practice question on Alternating Current (Transformers), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.