perpetual motion

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perpetual motion

n.
The hypothetical continuous operation of an isolated mechanical device or other closed system without a sustaining energy source.

perpetual motion

n
1. Also called: perpetual motion of the first kind motion of a hypothetical mechanism that continues indefinitely without any external source of energy. It is impossible in practice because of friction
2. Also called: perpetual motion of the second kind motion of a hypothetical mechanism that derives its energy from a source at a lower temperature. It is impossible in practice because of the second law of thermodynamics

perpet′ual mo′tion


n.
the motion of a theoretical mechanism that, without any losses due to friction or other forms of dissipation of energy, would continue to operate indefinitely at the same rate without any external energy being applied to it.
[1585–95]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.perpetual motion - motion that continues indefinitely without any external source of energyperpetual motion - motion that continues indefinitely without any external source of energy; impossible in practice because of friction
motion - a state of change; "they were in a state of steady motion"
References in periodicals archive ?
China co-production is a perpetual-motion machine of formulaic ideas that has a James Bondian reliance on showing off one exotic international location after another, albeit in the service of an adventure that serves up more slapstick than martinis.
Continuing his shadowboxing, Pacquiao briefly turned into a perpetual-motion machine as he threw combinations.
Earlier this month, the perpetual-motion machine that is the Republican Party rested on the topic of birth control.
Galt invents a motor that provides limitless energy from static electricity, what I dubbed the Objectivist Perpetual-Motion Machine.
In that sense, his description of that perpetual-motion machine that he offers resembles in each of its key facets Coda itself, whose unremitting twists and turns, fits and starts, truths and untruths remind us that narrative is a fundamentally dynamic form.
Johnny Carson would introduce him, and out Rodney would come, jerking, twitching, yanking at his tie, a perpetual-motion machine of anxiety; sweating, eyes bulging.
and while they were enormously concerned about the never-ending avalanche of slime thrown their way by this conservative perpetual-motion machine, I don't think I am breaking any press-stopping news when I report that they don't have a clue how to handle it.