Question

Determine the potential at a point 0.50 m (a) form a +20 μC point charge, (b) form a -20 μC point charge.

Answer 1

$$V=k\frac{q}{r}$$

(a)

$$V=9*10^9*\frac{20*10^{-6}}{0.50}=360000\:\rm V$$

(b)

$$V=9*10^9*\frac{-20*10^{-6}}{0.50}=-360000\:\rm V$$