JEE Main 2021 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 24 February 2021, Shift 2, Physics Q23

Question 23 of 90 in this shift, Physics question 23 of 30, Section B.

A uniform thin bar of mass 6 kg and length 2.4 meter is bent to make an equilateral hexagon. The moment of inertia about an axis passing through the centre of mass and perpendicular to the plane of hexagon is __________

\times 10^{-1}\ \mathrm{kg\ m^2}

Official answer

NTA final key.

Chapter: System of Particles and Rotational Motion
Topic: Moment of Inertia
Idea tested: MOI of a Polygonal Wire Loop

Same topic in other shifts

All Moment of Inertia questions

2 Apr 2026, Shift 2 · Q50Moment of inertia about an axis $AB$ for a rod of mass 40 kg and length 3 m is same as that of a solid sphere of mass of 10 kg and radius…MediumNumerical valueHas a figure
4 Apr 2026, Shift 1 · Q30A solid sphere of mass $M$ and radius $R$ is divided into two unequal parts. The smaller part having mass $M/8$ is converted into a sphere…MediumSingle correct
6 Apr 2026, Shift 1 · Q31A solid sphere of radius 4 cm and mass 5 kg is rotating (rotation axis is passing through the centre of the sphere) with an angular…MediumSingle correct
2 Apr 2025, Shift 1 · Q32Moment of inertia of a rod of mass 'M' and length 'L' about an axis passing through its center and normal to its length is ' $\alpha$ '. Now…MediumSingle correct
2 Apr 2025, Shift 2 · Q28The moment of inertia of a circular ring of mass $M$ and diameter $r$ about a tangential axis lying in the plane of the ring is :EasySingle correct
7 Apr 2025, Shift 1 · Q46A, B and C are disc, solid sphere and spherical shell respectively with same radii and masses. These masses are placed as shown in figure.…HardNumerical valueHas 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.