Q. The moment of inertia of a circular disc of radius 2 m and mass 2 kg, about an axis passing through its centre of mass is 2 kg – $m^{2}$. Its moment of inertia about an axis parallel to this axis and passing through its edge (in KM -$m^{2}$) is
A) 10
B) 8
C) 6
D) 4
Explanation
(a) Moment of inertia about the given axis $ie$, about $YY''$,
[image:7_image94.emf]
$I_{YY^{''}} = I_{XX^{''}} + MR^{2}$
$= 2 + 2 \times (2)^{2}$
$= 2 + 8$
$= 10\ kg - m^{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.