Question

The moment of inertia of a circular disc of radius $2m$ and mass $1kg$ about an axis passing through the centre of mass but perpendicular to the plane of the disc is $2{kgm}^2$. Its moment of inertia about an axis parallel to this axis but passing through the edge of the disc is............. (See the given figure).

• A. $10kg{m}^2$
• B. $6kg{m}^2$
• C. $8kg{m}^2$
• D. $4kg{m}^2$

Answer 1

Answer: (B)

According to parallel axis theorem
$I_{X.Y^{\prime }}=I_{XY}+M{R}^2$
$=2+(1)(2{)}^2$
$=6kg-m^2$