The maximum possible height of a mountain on earth is approximately (elastic limit of mountain rock =30 x 10⁷ Nm^-2, average density of mountain rock $=3\times {10}^3{\mathrm{kgm}}^{-3},g=10{\mathrm{ms}}^{-2}$)

Let's say the height of the mountain is h.

Stress at the bottom of the mountain is $\frac{Force}{Area}=\frac{mg}{A}=\frac{\rho \left(Ah\right)g}{A}=\rho gh$

This stress should be less than the elastic limit of mountain rock.

$\begin{array}{l}h\rho g=30\times {10}^7\\ h=\frac{30\times {10}^7}{3\times {10}^3\times 10}\\ h=10\mathrm{km}.\end{array}$