A system consists of two identical spheres each of mass 1.5 kg and radius 50 cm at the ends of a lig

Question

A system consists of two identical spheres each of mass 1.5 kg and radius 50 cm at the ends of a light rod. The distance between the centres of the two spheres is 5 m . What will be the moment of inertia of the system about an axis perpendicular to the rod passing through its midpoint ?

Professor PC Thomas Classes · Answer

By parallel axis theorem for each sphere: $I = 2[\frac{2}{5}mr^2 + md^2] = 2[\frac{2}{5}(1.5)(0.5)^2 + 1.5(2.5)^2] = 19.05 	ext{ kg m}^2$.