JEE Main 2021 — Magnetic Effects of Current Question with Solution
JEE Main 2021 (31 Aug Shift 1)
Question
A coil having turns is wound tightly in the form of a spiral with inner and outer radii and respectively. Find the magnetic field at centre, when a current passes through coil :
Choose an option
Show full solutionCorrect option: D
Correct answer
D
Step-by-step explanation
Recall the formula of the magnitude of the magnetic field in terms of current and permeability in free space, .
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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.