Question

State Bohr’s first postulate.

Answer 1

$\bold\red{Bhor's\: First\: postulate:-}$$<I>$Postulates of Niels Bohr Atomic Theory. The important postulates in his theory are, Electrons revolve round the nucleus with definite velocities in concentric circular orbits situated at definite distances from the nucleus. The energy of an electron in a certain orbit remains constant.

Answer 2

$\huge\colorbox{green}{Answer!}$

➡The electrons revolve around the nucleus in certain allowed circular orbits only and while in these orbits they do not radiate energy I. e electronic orbits are stable. The necessary centripetal force their circular motion is provided by the electrostatic attractive force between the positively charged nucleus and negatively and charged electrons. If Z is atomic number of the nucleus and r is the radius of any allowed electrons orbit.

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