JEE Main 2021PhysicsMagnetic Effects of CurrentMediumNumerical

JEE Main 2021 — Magnetic Effects of Current Question with Solution

JEE Main 2021 (27 Aug Shift 1)

Question

A uniform conducting wire of length is 24a, and resistance R is wound up as a current carrying coil in the shape of an equilateral triangle of side a and then in the form of a square of side a. The coil is connected to a voltage source V0. The ratio of magnetic moment of the coils in case of equilateral triangle to that for square is 1:y where y is ____________.

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Show full solutionCorrect answer: 3
Correct answer
3

Step-by-step explanation

4an1=24a

thus n1=6 turns

3an2=24a⇒n2=8 turns

M1M2=n1iA1n2iA2=6×a28×a2×34=31

M2M1=13=1y

y=3

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About this question

This is a previous-year question from JEE Main 2021, covering the Magnetic Effects of 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.