What is the magnitude of the electric force between a proton and an electron when they are at a distance of 7.31 angstrom from each other? 4.32x10-10 N You are correct. Your receipt no. is 164-5818 Previous Tries What is the magnitude of the electric force between two protons inside a nucleus when they are at a distance of 7.31 fermi from each other? 4.32 N You are correct. Your receipt no. is 164-8183 ? Previous Tries What is the magnitude of the electric force between an 'up' and a 'down' quark inside a proton when they are at a distance of 0.663 fermi from each other? (The up quark has an electric charge of (+2/3)e, the down quark has an electric charge of (-1/3)e, where e is the elementary charge.) Submit Answer Incorrect. Tries 9/99 Previous Tries