Bohr postulated that angular momentum of an electron revolving around the nucleus are quantized.
Angular momentum will only be an integral multiple of a constant value--
According to de- broglii,
\(\lambda=\frac {h}{mv}\)----(i)
The electron wave in an orbit must be in phase and so, circumference of an orbit must be integral multiple of the wavelength.
2πr = n\(\lambda\), or \(\frac1{\lambda}=\frac n{2\pi r}\)------(ii)
n = 1, 2, 3....
using equation (i) and (ii)
mvr = \(\frac{nh}{2\pi}\)
h = plank's constant, π = constant value
\(\therefore\) mvr = n x constant, n = 1, 2, 3....= (integer value)
Therefore,
mvr = angular momentum are quantized.
