Bohr's Quantization of Angular Momentum

msavg
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Bohr's second postulate says that it is only possible for an electron to move in an orbit for which its orbital angular momentum L is an integral multiple of \hbar.

Can somebody please derive and explain L= n\hbar for me?

I feel like a total dummy for not understanding this, but this is what I have so far:

L= mrv

L=pr, p= hf/c, f= w/2pi, where w is the angular frequency and w= v/r

L= \hbarwr/c = \hbarv/c ??

Yeah... I'm obviously missing something...
:\

Help?(Thank you in advance.)
 
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Welcome to physicsforums msavg,

the argument goes like this:
You interpret the electron as a standing wave as depicted http://www.personal.psu.edu/faculty/g/x/gxm21/A/Mayer-RingofFire_files/image003L.jpg . A circle has circumference C=2 \pi r and the condition for a standing wave is C=n \lambda. From these two equations we get n \lambda = 2 \pi r.

De Broglie says \lambda = h / p. Can you proceed?

(Edit: I changed the letter for circumference from L to C since it collides with the notation for the angular momentum)
 
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Edgardo said:
Welcome to physicsforums msavg,

the argument goes like this:
You interpret the electron as a standing wave as depicted http://www.personal.psu.edu/faculty/g/x/gxm21/A/Mayer-RingofFire_files/image003L.jpg . A circle has circumference C=2 \pi r and the condition for a standing wave is C=n \lambda. From these two equations we get n \lambda = 2 \pi r.

De Broglie says \lambda = h / p. Can you proceed?

(Edit: I changed the letter for circumference from L to C since it collides with the notation for the angular momentum)


Thank you.
:)

I knew I was missing something. This makes a whole lot more sense in context of standing waves.
 
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