The Gaussian gun is an arrangement of magnets and ball bearings (pictured in Fig. 1) such that—when the leftmost ball is released—the rightmost ball is ejected at high speeds. The device has been described in several articles on energy education. The sudden appearance of kinetic energy offers a productive context for considering a range of challenging ideas: the often-counterintuitive relationship between force and potential energy, the escape velocity for attractive forces, why energy is required to break bonds, and why energy is released when bonds form. Beyond these ideas, it is also useful for motivating the representation of a potential well and bound states for both quantum mechanics and chemistry.
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See the video at TPT Online, http://dx.doi.org/10.1119/1.5131114, under the Supplemental tab.
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2019
American Association of Physics Teachers
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