Question

Four charges are kept at the corners of a square ABCD as shown. The force on a positive charge placed at the centre of the square is

• A. $0$
• B. Along diagonal AC
• C. Along diagonal BD
• D. perpendicular to side AB

Answer 1

The correct option is D perpendicular to side AB

Force due to charge at $D$ and $B$ is along $\overrightarrow{F_{O}D}$ towards $\overrightarrow{B}$.

Force due to charge at $A$ and $C$ is along $\overrightarrow{F_{A}O}$ towards $\overrightarrow{A}$.

$\therefore$ Resultant displacement will be along $\overrightarrow{F}$ which is perpendicular to $AB$.