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Spin stabilized magnetic levitation

Martin D. Simon, UCLA Department of Physics, msimon@physics.ucla.edu,
Lee O. Heflinger, Torrance CA, and S. L. Ridgway, Santa Monica CA

Published in the American Journal of Physics, April 1997

copyright AAPT 1997

Abstract:

The stability of the Levitron cannot be explained if the top's axis has a fixed direction in space. Stability against flipping is not enough. Gyroscopic precession around the local magnetic field direction is necessary. An analysis and numerical integration of the equations of motion for an experimental stemless top that includes gyroscopic precession around the local magnetic field lines predict that the top will be supported stably up to spin speeds of about 3,065 rpm. An upper spin limit of 2779 rpm for this top is observed experimentally and explained as an adiabatic condition. Spin stabilized magnetic levitation is a macroscopic analog of magnetic gradient traps used to confine particles with a quantum magnetic moment.

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