# De broglie's explanation of bohr's second postulate

• gracy
In summary, the conversation discusses the relationship between the principle quantum number and the number of wavelengths in De-Broglie's hypothesis. However, this hypothesis was proven incorrect and the correct explanation lies in the solutions to Schroedinger's equation. Additionally, it is mentioned that for a wave function in one dimension, the principle quantum number is equal to the number of nodes of the wave function.

#### gracy

De broglie proved that angular momentum of particle can not have any value it has to have the value of nh/2pi and that's what Bohr's second postulate says but according to bohr that n in the formula is principal quantum number but according to de broglie n corresponds to number of waves.So why number of wavelength is same as principal quantum number?View this video from 8:00 to 8:08
why number of wavelength is same as principal quantum number.
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I know it has something to do with standing waves but not getting correct explanation.

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De-Broglie's hypothesis was simply an incorrect stepping stone to the correct quantum theory that came about at the end of 1926 when Dirac published his transformation theory - it's wrong - forget about it.

But within that model its pretty easy - if its some sort of wave only some waves can fit around a circle.

But like I say - its wrong - the correct answer is the solutions to Schroedinger's equation:
http://users.physik.fu-berlin.de/~pascual/Vorlesung/SS06/Slides/AMOL-L1d.pdf [Broken]

Thanks
Bill

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• vanhees71
Something that is true is that for a wave function in one dimension, the principle quantum number for a bound state is equal to the number of nodes of the wave function (places where the wave function is equal to zero). (With the exception that the wave function may also have a node wherever the potential is infinite.)

• vanhees71