JEE Main 2024 Physics question
Three balls of masses 2kg, 4kg and 6kg respectively are arranged at centre of the edges of an equilateral triangle of side 2 m. The moment of inertia of the system about an axis through the centroid and perpendicular to the plane of triangle, will be kg m².
Answer: 4
Solution
The distance from the centroid to each edge midpoint is the inradius 2/(2√3) = 1/√3, so I = (2 + 4 + 6)(1/3) = 4 kg m².