Question

A metal ball of radius a is surrounded by a thin concentric metal shell of radius b. The space between these electrodes is filled with a material of specific resistance $\rho$. Find the resistance of the inter electrode gap

Answer 1

$R={\int }_a^b\rho \frac{dr}{4\pi r^2}=\frac{\rho }{4\pi }[\frac{1}{a}-\frac{1}{b}]$