Question

The moment of inertia of a disc of mass $M$ and radius $R$ about an axis, which is tangential to the circumference of the disc and parallel to its diameter is

• A. $\frac{3}{2}MR^2$
• B. $\frac{2}{3}MR^2$
• C. $\frac{5}{4}MR^2$
• D. $\frac {4}{5}MR^2$

Answer 1

Answer: (C)

Moment of inertia of a disc about its diameter
$=\frac{1}{4} M R^{2}$
Using theorem of parallel axes,
$I=\frac{1}{4} M R^{2}+M R^{2}=\frac{5}{4} M R^{2} .$