Question

We have a hollow sphere and a solid sphere of equal radii and of the same material. They are heated to raise their temperature by equal amounts. How will the change in their volumes, due to volume expansions, be related? Consider two cases $\left(i\right)$ hollwo sphere is filled with air, $\left(ii\right)$ there is vacuum inside the hollow sphere.

Answer 1

For solid sphere volume coefficient of expansion is taken and for the hollow sphere, areal expansion of coefficient is taken. The volume coefficient is 1.5 times areal coefficient. So it will be 1.5 times expanded in case it is a vacuum inside. If it is air hollow will expand a bit more due to a coefficient of expansion of air.