JEE Main 2021PhysicsMagnetic Properties of MatterHardMCQ

JEE Main 2021 — Magnetic Properties of Matter Question with Solution

JEE Main 2021 (16 Mar Shift 1)

Question

A bar magnet of length 14 cm is placed in the magnetic meridian with its north pole pointing towards the geographic north pole. A neutral point is obtained at a distance of 18 cm from the center of the magnet. If BH=0.4 G, the magnetic moment of the magnet is 1 G=10-4 T

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Show full solutionCorrect option: C
Correct answer
C2.880 J T-1

Step-by-step explanation

i.e. 2μ04πmr2×7r=0.4×10-4

⇒2×10-7×m×772+1823/2×104=0.4×10-4

m=4×10-2×3733/214

⇒M=m×14 cm=m×14100=0.04×3733/214×14100

⇒M=4×10-4×7203.82=2.88 J T-1.

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About this question

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

A bar magnet of length 14   cm is placed in the magnetic meridian with its north pole pointing towards the geographic north pole. A ne… — JEE Main (2021) Solution · PrepSharp