Cyclotron Frequency of a Hydrogen Atom in a Field B

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The discussion centers on the cyclotron frequency of a hydrogen atom in a magnetic field B, focusing on the torque experienced by the electron. The equations presented derive the cyclotron frequency, showing that for orbital motion, the frequency is given by ω_p = qB/(2m) with g=1. The user notes a similarity between this result and the frequency derived from considering a single electron, ω = qB/m, despite the factor of 2 difference. The inquiry seeks to understand whether there is a deeper connection between these two cases or if the similarity is merely coincidental. The conversation highlights the importance of the ratio qB/m in obtaining correct dimensional analysis.
jackychenp
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Hi All,

For a hydrogen atom in the field B, torque on the electron is \tau =\mu Bsin\theta =\omega_pJsin\theta => \omega_p=gqB/(2m) If we only consider orbital motion (ignore spin), then g=1. So \omega_p=qB/(2m). (It follows the steps from Feynman's lectures VII section 34-3)
For a single electron in the field, qvB=v^2m/r => \omega=qB/m. I know these two cases are different, but why the results look the same (only a factor of 2 different). Is there any connection between them, or just coincidence?
 
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Getting the dimensions to come out right requires the ratio qB/m.
 
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