Physics 12
posted by solexgirl12 .
"Two small spheres are located 0.50m apart. Both have the same charge on them. If the repulsive force is 5.0N, what charge is on the spheres, in microcoulombs?"
I can begin to use my electrical force formula, but then I have two unknown charges. The anwser is 12 uC, but I am getting numbers like 3.98 x 10 to the 10. Can anyone help please?

5=9E9 q^2/.5^2
q= sqrt 1.39E10 = 12microC