Misplaced Pages

This is an old revision of this page, as edited by 213.253.40.87 (talk) at 03:47, 21 June 2002 ( Proponents of perpetual motion machines use a number of other terms to describe their inventions, including "free energy" and "over unity" machines.). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Perpetual motion machines are a class of hypothetical machines which produce energy "from nowhere." The existence of a perpetual motion machine is impossible according to current known laws of physics. Perpetual motion machines are divided into two subcategories, referred to as perpetual motion of the first kind and perpetual motion of the second kind.

A perpetual motion machine of the first kind is one which produces power without energy uptake. Such a machine would, once started, operate indefinitely. This is forbidden by the law of conservation of energy.

A perpetual motion machine of the second kind is one which converts heat completely into other forms of energy. Such a device would violate the second law of thermodynamics (see also entropy) and is therefore impossible.

The invention of perpetual motion machines is a favourite passtime of many crackpots, who often come up with elabourate Rube Goldberg machine designs which may appear to work on paper at first glance, but which have various flaws or obfuscated external power sources that render them useless in practice. This sort of invention has become common enough that the US Patent Office has made an official policy of refusing to grant patents for perpetual motion machines.

Proponents of perpetual motion machines use a number of other terms to describe their inventions, including "free energy" and "over unity" machines.

External links:

• Eric's History of Perpetual Motion and Free Energy Machines