Question

How bohr postulated that angular momentum of electron around the nucleus is integral multiple of h cross?

Answer 1

Bohr's postulates clearly says that angular mommentum of an electron is quantised
so the revolution of electron is restricted to only permitted orbits.
Again the orbits are denoted k,l,m,n those are in numbers like 1,2,3,4 .....
so bohr's postulates says the revolution if electron around nucleis is integral multiple of
$h \div 2\pi$