Question

A solid cylinder has mass M , length L and radius R .The moment of inertia of this cylinder about a generator is

• A. $M\left(\frac{L^2}{12}+\frac{R^2}{4}\right)$
• B. $\frac{M{L}^2}{4}$
• C. $\frac{1}{2}M{R}^2$
• D. $\frac{3}{2}M{L}^2$

Answer 1

The correct option is C $\frac{1}{2}M{R}^2$

$\begin{array}{c}\text{Generator implies axis of cylinder}perpendicular\text{to circular}\\ \text{faces the cylinder behaves as disc for}\\ \text{M.I about its axis}\left(\text{ie}\frac{M{R}^2}{2}\right)\end{array}$