Question

Write the expression for electrostatic force in vector form and explain the terms.

Answer 1

If $q_1$ and $q_2$ are placed on A & B then Columb's Force
$\overrightarrow{F}=\frac{1}{4\pi {\epsilon }_0}.\frac{q_1{q}_2}{{r_1}^2}.{\hat{r}}_{21}$ (Force on 2 due to 1)
Here ${\hat{r}}_{21}$ is unit vector $\theta$ position
$r_{21}={\hat{r}}_2-{\hat{r}}_1$