Assume that there is no repulsive force between the electrons in an atom but the force between positive and negative charges is given by Coulomb’s law as usual. Under such circumstances, calculate the ground state energy of a He-atom.
For H atom Z=1 and n=1 ∴En=8ε0212h2−mge4=13.6eV For He- atom, Z=4 and n=1 ∴En=8ε0212h2−mge4=−4×13.6=54.4eV
