Q11 of 149 Page 194

A circular disc A of radius r is made from an iron plate of thickness t and another circular disc B of radius 4r is made from an iron plate of thickness t/4. The relation between the moments of inertia IA and IB is

To solve this let us assume A and B as combinations of many small discs of thickness dt. The moment of inertia will be,




dm is the mass of that little orange circle. If ρ be the density then,








Similarly calculating for B;







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