# Prove that thickness of a disc of uniform strength is given by

$t={t}_{0}exp\left[\frac{-\rho {w}^{2}{r}^{2}}{2\sigma}\right]$

Where t_{0 }is the thickness at r = 0

$t={t}_{0}exp\left[\frac{-\rho {w}^{2}{r}^{2}}{2\sigma}\right]$

Where t_{0 }is the thickness at r = 0