Question

Figure shows a thin metallic triangular sheet $A B C .$ The mass of the sheet is $M$. The moment of inertia of the sheet about side $A C$ is:

• A. $\frac{M l^{2}}{18}$
• B. $\frac{M l^{2}}{12}$
• C. $\frac{M l^{2}}{6}$
• D. $\frac{M l^{2}}{4}$

Answer 1

Answer: (B)

$h=\frac{l}{\sqrt{2}}$
$I_{A C}=\frac{1}{6} M h^{2}=\frac{M l^{2}}{12}$