Shown in the figure is a hollow ice-cream cone (it is open at top). If its mass is , radius of its top is and height, , then its moment of inertia about its axis is

Shown in the figure is a hollow ice-cream cone (it is open at top). If its mass is , radius of its top is and height, , then its moment of inertia about its axis is

It can be assumed as several parts of discs having different radius, so
From diagram
From equation (i), (ii) and (iii)
Asked in: JEE Main 2020 (06 Sep Shift 1)