JEE Main 2020PhysicsMagnetic Effects of CurrentHardMCQ

JEE Main 2020 — Magnetic Effects of Current Question with Solution

JEE Main 2020 (03 Sep Shift 1)

Question

Magnitude of magnetic field (in SI units) at the centre of a hexagonal shape coil of side 10 cm,50 turns and carrying currentI  (Ampere) in units of μ0Iπ is :

Choose an option

Show full solutionCorrect option: C
Correct answer
C5003

Step-by-step explanation

The magnetic field due to the current-carrying finite length wire is given by

B=μ0I4πRsinθ1+sinθ2

Here for hexagonal shape coil, θ1=θ2=30°.

So, the net magnetic field at the centre will be B=50×6×μ0i4π10100cos 30°sin 30°+sin 30°

B=2×75×10μ0i3π12+12

B=15003μ0iπ   =5003μ0iπ

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About this question

This is a previous-year question from JEE Main 2020, 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.