It can be assumed as several parts of discs having different radius, so

I=∫dl=∫dm(r2)
From diagram
yr=tanθ=HR
r=HR⋅y
dm=ρ(πr2)dy
From equation (i), (ii) and (iii)
I=2MR2
JEE Main 2020 — Physics Mechanics
Shown in the figure is a hollow ice-cream cone (it is open at top). If its mass is M, radius of its top is R and height, H, then its moment of inertia about its axis is

Held on 6 Sept 2020 · Verified 6 Jul 2026.
2MR2
4M(R2+H2)
3MH2
3MR2
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