Which one of the following is considered as the main postulate of Bohr's model of atom:
(1) Protons are present in the nucleus
(2) Electrons are revolving around the nucleus
(3 )Centrifugal force produced due to the revolving electrons balances the force of attraction between the electron and the protons
(4) Angular momentum of electron is an integral multiple of h/ 2 Π
Ans: Angular momentum of electron is an integral multiple of h/ 2 Π