Physics - Rotation Question with Solution | TestHub

Seven pennies are arranged in a hexagonal, planar pattern so as to touch each neighbor, as shown in the figure below. Each penny is a uniform disk of mass $\mathrm{m}=2\mathrm{kg}$ and radius $\mathrm{r}=1\mathrm{m}$. What is the moment of inertia of the system (in $\mathrm{kg}-{\mathrm{m}}^2$ ) of seven pennies about an axis that passes through the center of the central penny and is normal to the plane of the pennies ?