Chapter 6.6, Problem 24ES

It follows from Coulomb’s law in physics that two like electrostatic charges repel each other with a force inversely proportional to the square of the distance between them. Suppose that two charges $A$ and $B$ repel with a force of $k$ newtons when they are positioned at points $A\left(-a,0\right)$ and $B\left(a,0\right)$ , where a is measured in meters. Find the work $W$ required to move charge $A$ along the $x\text{-axis}$ to the origin if charge $B$ remains stationary.