JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 17 March 2021, Shift 1, Physics Q4

Question 4 of 90 in this shift, Physics question 4 of 30, Section A.

A solenoid of 1000 turns per metre has a core with relative permeability 500. Insulated windings of the solenoid carry an electric current of 5 A. The magnetic flux density produced by the solenoid is : (permeability of free space

=4\pi\times10^{-7}

H/m)

(1) $10^{-4}\pi$ T
(2) $2\times10^{-3}\pi$ T
(3) $\frac{\pi}{5}$ T
(4) $\pi$ TOfficial answer

Official answer

Option 4

NTA final key.

Chapter: Moving Charges and Magnetism
Topic: Ampere's Circuital Law
Idea tested: Ideal Infinite Solenoid

Same idea in other shifts

Asked 5× in all

5 Apr 2024, Shift 2 · Q57A solenoid of length 0.5 m has a radius of 1 cm and is made up of 'm' number of turns. It carries a current of 5 A. If the magnitude of…EasyNumerical value
8 Apr 2023, Shift 1 · Q58The magnetic intensity at the center of a long current carrying solenoid is found to be $1.6\times10^3\ \mathrm{Am^{-1}}$ . If the number…EasyNumerical value
25 Jun 2022, Shift 2 · Q41A long solenoid carrying a current produces a magnetic field $B$ along its axis. If the current is doubled and the number of turns per cm…EasySingle correct
18 Mar 2021, Shift 1 · Q3Four identical long solenoids A, B, C and D are connected to each other as shown in the figure. If the magnetic field at the center of A…MediumSingle correctHas a figure

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.