A point charge with charge q1 is held stationary at the origin. A second point charge with charge q2 moves from the point (x1, 0) to the point (x2, y2).

How much work W is done by the electrostatic force on the moving point charge?

Express your answer in joules. Use k for Coulomb’s constant (k=1/4(pi)(epsilon).

Any help will be greatly appreciated!

Answer:

The way the question is stated, emphasis is given on moving the charge q2 from some point to some other point. The work done would be the potential energy difference between the two configrations. It will be assumed that the charge will be moved infinitely slowly so that there is no kinetic energy of the cahrge at any instant.

So work done = kq1q2{1/[x1] – 1/sqrt[(x2)^2+(y2)^2]} Joules