The moment of inertia of a uniform circular disc of radius `R` and mass `M` about an axis passing from the edge of the disc and normal to the disc is.

Options

A. `MR^2`
B. `(2)/(5) MR^2`
C. `(3)/(2) MR^2`
D. `(1)/(2) MR^2`

Answer

C

Explanation

( c) The moment of inertia about an axis passing through centre of mass of disc and perpendicular to its plane is
`I_(CM) = (1)/(2) MR^2`
where `M` is the mass of disc and `R` its radius According to theorem of parallel axis. `MI` of circular disc about an axis touching the disc at its diameter and normal to the disc is
`I = I_(CM) + MR^2`
=`(1)/(2) MR^2 + MR^2 = (3)/(2) MR^2`.