14 test

Using vector notation, the Coulomb force [latex]\vec F_{12}[/latex] exerted on [latex]q_1[/latex] due to [latex]q_2[/latex] is expresses as

[latex]\begin{equation} \vec F_{12} = \frac{1}{{4\pi \varepsilon _0 }}\frac{{q_1 q_2}}{{r_{12}^2 }}\hat r_{12} \label{Coulomb1} \end{equation}[/latex]