Perpetual motion
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Perpetual motion is the motion of bodies that continues forever in an unperturbed system. A perpetual motion machine is a hypothetical machine that can do work indefinitely without an external energy
October 1920 issue of Popular Science magazine, on perpetual motion. Although scientists have established that perpetual motion is incompatible with the laws of physics, the idea continues to capture the imagination of inventors.
Perpetuum mobile of Villard de Honnecourt (about 1230).
Perpetual motion wheels from a drawing by Leonardo da Vinci
Conservation of energy
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The law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be conserved over time. In the case of a closed system, the principle says that the
Perpetual motion
…violates either the first law of thermodynamics, the second law of thermodynamics, or both. The first law of thermodynamics is a version of the law of conservation of energy. The second law can be phrased in several different ways, the most intuitive of which is that heat flows spontaneously from hotter to colder places…
Gottfried Leibniz
Daniel Bernoulli
Emilie du Chatelet
Gaspard-Gustave Coriolis