Imagine three point charges sitting in a space. To determine the electric potential at some point P in that space (other than the locations of the point charges), you need to Imagine three point charges sitting in a space. To determine the electric potential at some point P in that space (other than the locations of the point charges), you need to sum up the electric potentials of each charge, at the point P. sum up the electric potential energy of the three pairs of point charges sum of the electric field magnitudes of each charge, at that point P. compute the magnitude of the electric field at point P