The goal of this paper is to make more widely known an eye-catching demonstration experiment in which a hanging conducting can is made to spin when placed near the iron core of an Elihu Thomson “jumping ring” apparatus. An explanation is given based on Faraday’s law of induced voltages and the magnetic forces due to the core’s fields interacting with the induced currents.
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For a video file of the demonstration, please see [supplementary material] available under the “References” tab at TPT Online, http://dx.doi.org/10.1119/1.4965272 .
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For access to this appendix, please see [supplementary material] available under the “References” tab at TPT Online, http://dx.doi.org/10.1119/1.4965272 .
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