Question

What is the electric field due to a point charge of 20µC at a distance of 1 meter away from it?

How much charge experiences a force of 5.0 x10^-3 N due to an electric field of 10 N/C?

Answer 1

Electric field

$E=\frac{kq}{r^²}$

$$E=\frac{9\times10^9\times20\times10^{-6}}{1^2}=18\times10^4N/C$$

Force

$F=qE$

$q=\frac{F}{E}$

$q=\frac{5\times10^{-3}}{10}=5\times10^{-4}C$