# Hollow Sphere

## Hollow Sphere

A hollow sphere is what is left of a sphere with radius $$r_{\scriptsize{2}}$$, when a sphere with radius $$r_{\scriptsize{1}}$$ has been removed from it, the two spheres having the same centre and $$r_{\scriptsize{1}}$$ < $$r_{\scriptsize{2}}$$.

### Formulas

The volume V of a hollow ball is:

$$V = \dfrac{4\pi (r_{\scriptsize{2}}^3~ – ~r_{\scriptsize{1}}^3)}{3}$$