I can't seem to figure out how to do this problem. I've tried the equation for coulomb's law, but I can't get the right answer. If somebody can just help me with setting the problem up. Two objects ar rubbed against each other. Object B gains a charge of -5 nano-coulombs. What is the electric force between the two objects when the distance between them is 3.0 cm? Also, how do I convert the nano-coulombs to coulombs?