To solve this problem we will apply the concepts related to electric potential and electric potential energy. By definition we know that the electric potential is determined under the function:
[tex]V = \frac{k_e q}{r}[/tex]
[tex]k_e[/tex] = Coulomb's constant
q = Charge
r = Radius
At the same time
[tex]U = \frac{k_e q_1q_2}{r}[/tex]
The values of variables are the same, then if we replace in a single equation we have this expression,
[tex]U = Vq[/tex]
If we replace the values, we have finally that the charge is,
[tex]V = 800V[/tex]
[tex]q = 1\mu C[/tex]
[tex]U = (800V)(1*10^{-6}C)[/tex]
[tex]U = 8*10^{-4}J[/tex]
Therefore the potential energy of the system is [tex]8*10^{-4} J[/tex]
