Q: The moment of inertial of a rectangular lamina about an axis perpendicular to the plane and passing through its centre of mass is
(a) $\frac{M}{12} (l^2 + b^2) $
(b) $\frac{M}{3} (l^2 + b^2) $
(c) $\frac{M l}{12} $
(d) $\frac{M}{12} (l + b) $
Ans: (a)