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Updated: Jul 4, 2026
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Published on: June 28, 2018
Dipole in a magnetic field, work, and quantum spin
1Physics Department, Cleveland State University, Cleveland, OH 44114, USA. deissler@zubetube.com
Summary
The magnetic field
Area of Science:
- Atomic and Molecular Physics
- Classical Electrodynamics
Background:
- Nonuniform magnetic fields exert forces on magnetic dipoles.
- The behavior of atoms and classical magnetic dipoles in such fields is crucial for understanding quantum phenomena and classical mechanics.
Purpose of the Study:
- To analyze the behavior of atoms and classical magnetic dipoles in nonuniform magnetic fields.
- To investigate the work done by magnetic fields on electron-orbital and electron-spin contributions to magnetic moments.
- To explore the implications of electron intrinsic rotational kinetic energy.
Main Methods:
- Theoretical analysis of atomic and classical magnetic dipole motion in nonuniform magnetic fields.
- Examination of energy conservation principles.
- Consistency check with the Dirac equation for electron spin.
Main Results:
- Magnetic fields do no work on the electron-orbital magnetic moment contribution.
- Work done on the electron-spin contribution depends on intrinsic rotational kinetic energy.
- Classical objects exhibit simple harmonic motion in a constant magnetic field gradient.
- Total kinetic energy (translational + rotational) is conserved for classical objects.
Conclusions:
- Electron intrinsic rotational kinetic energy, consistent with the Dirac equation, can explain phenomena like the Stern-Gerlach experiment without magnetic field work.
- Classical magnetic dipoles oscillate harmonically, conserving total kinetic energy in nonuniform fields.
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