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Register a new userPendulums, Drops and Rods: a physical analogy
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A liquid meniscus, a bending rod (also called elastica) and a simple pendulum are all described by the same non-dimensional equation. The oscillatory regime of the pendulum corresponds to buckling rods and pendant drops, and the high-velocity regime corresponds to spherical drops, puddles and multiple rod loopings. We study this analogy in a didactic way and discuss how, despite this common governing equation, the three systems are not completely equivalent. We also consider the cylindrical deformations of an inextensible, flexible membrane containing a liquid, which in some sense interpolates between the meniscus and rod conformations.
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