Find the moment of inertia of a disc of mass 3 kg and radius 50 cm about the following axes.
axis touching the edge and perpendicular to the plane of the disc and

Explanation

The mass, M = 3 kg, radius R = 50 cm = `50 × 10^(−2)` m = 0.5 m
The moment of inertia (I) about an axis touching the edge and perpendicular to the plane of the disc by parallel axis theorem is,

`I=I_(C)+Md^(2)`
where, `I_(C)=(1)/(2)MR^(2)` and d = R
`I=(1)/(2)MR^(2)+MR^(2)=(3)/(2)MR^(2)`
`I=(3)/(2)xx3xx(0.5)^(2)=1.5xx3xx0.5xx0.5`
`I=1.125kgm^(2)`