Niels Bohr studied in Rutherford’s laboratory for several
months in 1912 and he was convinced about the validity of Rutherford
nuclear model Faced with the dilemma as discussed above, Bohr, in
1913, concluded that in spite of the success of electromagnetic theory in
explaining large-scale phenomena, it could not be applied to the processes
at the atomic scale It became clear that a fairly radical departure from
the established principles of classical mechanics and electromagnetism
would be needed to understand the structure of atoms and the relation
of atomic structure to atomic spectra Bohr combined classical and early
quantum concepts and gave his theory in the form of three postulates