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perpetual motion

perpetual motion the motion of a hypothetical machine which, once activated, would run forever unless subject to an external force or to wear; although impossible according to the first and second laws of thermodynamics, the development of such a mechanism has been attempted by many inventors. The Dutch philosopher and inventor Cornelis Drebbel (1572–1634), in England in the early 17th century, was said to have perfected such a device, which he presented to the king, and which became one of the sights of the day.

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perpetual motion

perpetual motion Hypothetical machine that continues to work without any energy being supplied. Such a machine would require either the complete elimination of friction, or would have to violate the laws of thermodynamics.

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"perpetual motion." World Encyclopedia. . Encyclopedia.com. 17 Aug. 2018 <http://www.encyclopedia.com>.

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