Question

Find the moment of inertia (in ${\text{kg-m}}^2$) of a hollow cylinder of radius $3\text{m}$ and mass $3\text{kg}$, about an axis passing through the centre of the hollow cylinder. [Assume thickness of the hollow cylinder to be small]

• A. $13.5$
• B. $27$
• C. $54$
• D. $6.75$

Answer 1

The correct option is B $27$

Given,
Mass of hollow cylinder $\left(M\right)=3\text{kg}$
Radius of hollow cylinder $\left(r\right)=3\text{m}$
Moment of inertia of a hollow cylinder $I=M{r}^2$
$=\left(3\right)(3{)}^2$
$=27{\text{kg-m}}^2$