Changes

==Origin==

==Origin==

[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English] perpetuel, from Anglo-French, from [[Latin]] perpetuus uninterrupted, from per- through + petere to go to

[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English] perpetuel, from Anglo-French, from [[Latin]] perpetuus uninterrupted, from per- through + petere to go to

*[http://en.wikipedia.org/wiki/14th_century 14th Century]

*[https://en.wikipedia.org/wiki/14th_century 14th Century]

==Definitions==

==Definitions==

*1a : continuing forever : everlasting <perpetual motion>  

*1a : continuing forever : everlasting <perpetual motion>  

'''Perpetual motion''' describes [[hypothetical]] [[machines]] that operate or produce useful [[work]] indefinitely and, more generally, hypothetical [[machines]] that produce more [[work]] or [[energy]] than they consume, whether they might operate indefinitely or not.

'''Perpetual motion''' describes [[hypothetical]] [[machines]] that operate or produce useful [[work]] indefinitely and, more generally, hypothetical [[machines]] that produce more [[work]] or [[energy]] than they consume, whether they might operate indefinitely or not.

There is undisputed [http://en.wikipedia.org/wiki/Scientific_consensus scientific consensus] that perpetual motion would [[violate]] either the [http://en.wikipedia.org/wiki/First_law_of_thermodynamics first law of thermodynamics], the [http://en.wikipedia.org/wiki/Second_law_of_thermodynamics second law of thermodynamics], or both. Machines which comply with both laws of thermodynamics but [[access]] [[energy]] from obscure [[sources]] are sometimes referred to as perpetual motion machines, although they do not meet the [[standard]] criteria for the name.

There is undisputed [https://en.wikipedia.org/wiki/Scientific_consensus scientific consensus] that perpetual motion would [[violate]] either the [https://en.wikipedia.org/wiki/First_law_of_thermodynamics first law of thermodynamics], the [https://en.wikipedia.org/wiki/Second_law_of_thermodynamics second law of thermodynamics], or both. Machines which comply with both laws of thermodynamics but [[access]] [[energy]] from obscure [[sources]] are sometimes referred to as perpetual motion machines, although they do not meet the [[standard]] criteria for the name.

Despite the [[fact]] that successful perpetual motion devices are [[physically]] impossible in terms of our current [[understanding]] of the [[laws]] of [[physics]], the pursuit of perpetual motion remains [[popular]].[http://en.wikipedia.org/wiki/Perpetual_motion]

Despite the [[fact]] that successful perpetual motion devices are [[physically]] impossible in terms of our current [[understanding]] of the [[laws]] of [[physics]], the pursuit of perpetual motion remains [[popular]].[https://en.wikipedia.org/wiki/Perpetual_motion]

[[Category: Physics]]

[[Category: Physics]]