perpetual motion

views updated May 17 2018

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.

perpetual motion

views updated Jun 11 2018

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.