अपने मूल अवस्था (ground state) में एक हाइड्रोजन-सदृश परमाणु (या आयन) की कुल ऊर्जा -54.4 eV है। इस आयन/परमाणु की पहचान कीजिए।

In the first excited state of a hydrogen atom, the energy of its electron is -3.4 eV. The radial distance of the electron from the nucleus in this state is approximately: (Take 1 eV = 1.6 × 10-19 J, e = 1.6 × 10-19 C, and 14πε0 = 9 × 109 N m2/C2)

The second postulate of Bohr's atomic model (quantization of angular momentum) can be explained on the basis of which theory?