Figure shows equi-potential surfaces for a two charges system. At which of the labeled points point will an electron have the highest potential energy?
Potential energy when electron at B is WB=k(−e)(−q)rb=kqerb where rb be the distance between −e and −q.
similarly, WC=k−qerc and WD=k−qerd and WA=0
Thus, the highest potential energy point will be B.