Consider a solid sphere and a hollow sphere, both of mass $M$, radius $R$ and initially at rest, which start rolling down the same inclined plane without slipping. At the bottom of the inclined plane, the ratio of speeds $\mathrm{V}^{\text {solid }} / \mathrm{V}^{\text {hollow }}$ is
- $1$
- $\sqrt{12 / 7}$
- $\sqrt{10 / 7}$
- $\sqrt{25 / 21}$
[Note : The moment of inertia about any diameter for a solid sphere is $(2 / 5) \mathrm{MR}^{2}$, and for a hollow sphere $(2 / 3) \mathrm{MR}^{2}$ ]
