Electrostatic Force Between a Sphere at Constant Voltage and Another at Fixed Charge

We analyze the electrostatic force between two conducting spheres where one sphere is held at a constant voltage and the other sphere has a fixed amount of charge. We find interesting results where, for high size asymmetry, the force between the spheres can first increase with sphere separation before decreasing eventually. For certain separations, decreasing the charge on the second sphere can increase the electrostatic force. increase with sphere separation before decreasing eventually.