Answer to Question #304228 in Electricity and Magnetism for Sim

Question

A spherical conductor of radius 8 cm has a uniform surface charge density of 0.1 nC/m^2. Determine the electric field: a) on the surface of the conductor; b) at a distance of 10 cm from the centre of the conductor.

Answer 1

The electric field: a) on the surface of the conductor

$$E=\frac{q}{4\pi\epsilon_0r^2}=\frac{\sigma}{\epsilon_0}$$

$$E_1=\frac{0.1*10^{-9}}{8.85*10^{-12}}=11\:\rm V/m$$

b) at a distance of 10 cm from the centre of the conductor

$$E_2=E_1\frac{r_1^2}{r_2^2}=11*\frac{8^2}{10^2}=7.2\:\rm V/m$$