Physics - Magnetism Question with Solution | TestHub

$\mathrm{ABCD}$ is a rectangle. At corners $\mathrm{B},\mathrm{C}$ and $\mathrm{D}$ of the rectangle are placed charges $+10\times 10^{-12}\mathrm{C}$, $-20\times 10^{-12}\mathrm{C}$ and $10\times 10^{-12}\mathrm{C}$ respectively. Calculate the potential at the fourth corner. The side $\mathrm{AB}=4\mathrm{cm}$ and $\mathrm{BC}=3\mathrm{cm}$