Proof using mainly classical mechanics

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Homework Help Overview

The discussion revolves around the challenge of quantizing angular momentum (L) using classical mechanics principles, while avoiding reliance on quantum mechanics concepts. The original poster references equations related to classical mechanics and attempts to reconcile them with quantum results, particularly in the context of energy levels in atomic systems.

Discussion Character

  • Mixed

Approaches and Questions Raised

  • The original poster attempts to derive quantization of angular momentum without invoking quantum mechanics, expressing confusion over how to integrate classical mechanics with established quantum results. Some participants question the feasibility of this approach, while others provide equations that may be relevant to the discussion.

Discussion Status

The conversation is ongoing, with participants exploring various equations and their implications. There is an acknowledgment of the difficulty in deriving certain energy equations using classical methods, and some participants are sharing insights and equations that could potentially aid in the exploration.

Contextual Notes

Participants are grappling with the constraints of classical mechanics while trying to incorporate results derived from quantum mechanics, leading to questions about the validity of certain terms and relationships in their equations.

physicsjock
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Hey,

http://img822.imageshack.us/img822/407/25944209.jpg
[itex]\begin{align}<br /> & \frac{m{{v}^{2}}}{r}=\frac{Z{{e}^{2}}}{4\pi {{\varepsilon }_{0}}{{r}^{2}}} \\ <br /> & L=\frac{Z{{e}^{2}}}{4\pi {{\varepsilon }_{0}}v} \\ <br /> \end{align}[/itex]

and I know by using the v derived using Bohr's equations it will give the answer but that v is derived using L=nh so it's not that simple.

I can't figure out how to quantize L without breeching the conditions of the question. Would anyone have any ideas?

Thanks in advanced
 
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You want to quantise L without using any premises of quantum mechanics?
 
Haha, that's what's messing this up for me, that's how I've been thinking, I don't see how you can get a result like that using means that don't agree with the result.

There's a few results I just found which I can use,


[itex]E=-\frac{hR}{{{n}^{2}}};\frac{{{\left| E \right|}^{3}}}{{{\omega }^{2}}}=\frac{{{Z}^{2}}m{{\alpha }^{4}}}{8}=\frac{R{{h}^{3}}}{16{{\pi }^{2}}}=\operatorname{Constant},\alpha =\frac{{{e}^{2}}}{4\pi {{\varepsilon }_{0}}}[/itex]

At first glance the first equation looks like the most useful but h and n and inversely related, and I can't shake the squared on the n.
 
If you're using only classical ideas, where did the n and the h come from in E?
 
It was derived using Ritz principal and Rydbergs formula

[itex]{{E}_{n}}-{{E}_{m}}=h\,{{v}_{nm}}[/itex]

λ-1=[itex]R\left( \frac{1}{{{m}^{2}}}-\frac{1}{{{n}^{2}}} \right)[/itex]

So I'm trying to find a way to quantize L using classical mechanics in conjunction with the results I posted before
 
I'm having trouble deriving

[itex]E=-\frac{hR}{{{n}^{2}}}[/itex]

as well,

This is what I've been doing,
[itex]\begin{align}<br /> & \frac{1}{\lambda }=R\left( \frac{1}{{{m}^{2}}}-\frac{1}{{{n}^{2}}} \right) \\ <br /> & \frac{ch}{\lambda }=vh=E=chR\left( \frac{1}{{{m}^{2}}}-\frac{1}{{{n}^{2}}} \right) \\ <br /> & E=-chR\left( \frac{1}{{{n}^{2}}} \right) \\ <br /> \end{align}[/itex]

It's supposed to be the ionization energy, so the 1/m disappears because you take the limit as m -> infinity

Not sure how to get rid of the c
 

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