“every matter has a wave associated with it.”

Based on this hypothesis, de-Broglie, suggested a model of atom in which energy levels & orbits of Bohr model were retained but the electron in various orbits behaved as a matter wave of wavelength :

The path of the electron can be satisfy only if the length of the orbit i.e. circumference (2πr) is an integral of de-Broglie wavelength λ .

If it is not so, the electron waves will be out of phase with itself which will continuously change and as a result the stationary orbit will not be possible.

This is Bohr’s quantum Condition, i.e.

“the electron will rotate only in those orbits whose angular momentum is integral multiple of h/2π”