One quarter sector is cut from a uniform circular disc ofradius R. This sector has mass M. It is made to rotate about a line perpendicular to its plane and passing through the centre of the original disc. Its moment of inertia about the axis of rotation is

Options

A. `1/2MR^(2)`
B. `1/4MR^(2)`
C. `1/8MR^(2)`
D. `sqrt2MR^(2)`

Answer

A

Explanation

This sector is cut from the disc of mass 4M and radius R.
Moment of inertia of that disc = `1/2(4M)R^(2)`
Moment of inertia of sector=`1/2(4M)R^(2)xx1/4=1/2MR^(2)`