A charge $( - q)$ and another charge $( + Q)$ are kept at two points $A$ and $B$ respectively. Keeping the charge $( + Q)$ fixed at $B$, the charge $( - q)$ at $A$ is moved to another point $C$ such that $ABC$ forms an equilateral triangle of side $l$. The net work done in moving the charge $( - q)$ is
d (d) According to figure, potential at $A$ and $C$ are equal. Hence work done in moving $-q$ charge from $A$ to $C$ is zero.
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