Past exam of the mathematics course of the University of Oxford / 2017 / Prelims / Mathematics IV resit / 6 / c / Solution

For a uniform solid cylinder, set $a=0$ in the moment of inertia formula, givingFor the hollow cylinder, $a>0$ makes the denominator larger:on a downward incline with $\sin \phi >0$. Thus the solid cylinder accelerates faster, assuming rolling without slipping for both. More of the hollow cylinder's mass lies far from the rotation axis, increasing its moment of inertia relative to $M{b}^2$.