JEE Main 2018PhysicsAlternating CurrentEasyMCQ

JEE Main 2018 — Alternating Current Question with Solution

JEE Main 2018 (16 Apr Online)

Question

A power transmission line feeds input power at 2300 V to a step-down transformer with its primary windings having 4000 turns giving the output power at 230 V. If the current in the primary coil of the transformer is 5 A and its efficiency is 90 %, the output current would be:

Choose an option

Show full solutionCorrect option: A
Correct answer
A45 A

Step-by-step explanation

Efficiency, η=0.9=PsPp

VsIs=0.9 × VpIp

Is=0.9 ×2300 ×5230=45 A

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About this question

This is a previous-year question from JEE Main 2018, covering the Alternating Current chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.