Coulomb's law is given by F=Kq1q2r2, where F is the force, K is a constant, q1 and q2 are the charges on the two bodies, and r is the distance between them. Rewrite the formula for Coulomb's law to solve for r.

To rewrite the formula, pretend as if you're solving for r. To do so, try to get r alone on one side of the equation. To do so, you will divide both sides by everything else:

F = Kq1q2r^2

F/Kq1q2 = r^2

Then, take the square root of both sides:

square root (F/Kq1q2) = square root r