Question

Write Coulomb's law in vector form for the force of attraction or repulsion between two point charges.

Answer 1

Let the two charges $q_1$ and $q_2$ be placed at a separation $r$.
Force acting on $q_2$ due to $q_1$ is given by $\overrightarrow{F}=\frac{1}{4\pi {ϵ}_o}.\frac{q_1{q}_2}{|\overrightarrow{r}{|}^3}\overrightarrow{r}$