Question

Find moment of inertia about axis shown which is equidistant from both spheres

Answer 1

$I=[\frac{2}{5}Mr^{2}+M(0.2)^{2}]\times 2$

$=[\frac{2}{5}\times 2\times (0.1)^{2}+2\times (0.2)^{2}]\times 2$

$=[\frac{4}{500}+\frac{8}{100}]\times 2$

$=\frac{44\times 2}{500}=\frac{88}{500}(kg-m^{2})$

So, the correct answer is $\frac{88}{500} (kg-m^{2})$