JEE Main 2018PhysicsMagnetic Effects of CurrentMediumMCQ

JEE Main 2018 — Magnetic Effects of Current Question with Solution

JEE Main 2018 (15 Apr)

Question

A Helmholtz coil has a pair of loops, each with N turns and radius R . They are placed coaxially at distance R and the same current I flows through the loops in the same direction. The magnitude of the magnetic field at P, midway between the centres A and C, is given by [Refer to figure given below]:

Choose an option

Show full solutionCorrect option: D
Correct answer
D 8Nμ0I53/2R

Step-by-step explanation

Magnetic field at point P, due to both coils, Bp=2μ0NIR22R2+R243/2 = μ 0 NI R 2 5 3/2 8 R 3 = 8Nμ0I53/2R.
 

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About this question

This is a previous-year question from JEE Main 2018, 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.