Change of Internal State of An Isolated System
If an isolated system is left long enough, it will reach a state of thermal equilibrium, in which its temperature will be uniform throughout, but not necessarily a state of thermodynamic equilibrium, if there is some structural barrier that can prevent some possible processes in the system from reaching equilibrium. An isolated system can change its temperature or its spatial distribution of temperature by changing the state of Longley, R.G. Van Name, Longmans, Green & Co., New York, 1928, volume 1, pages 55-353, particularly pages 144-150. A system prepared as a mixture of petrol vapour and air can be ignited by a spark and produce carbon dioxide and water; if this happens in an isolated system, it will increase the temperature of the system, and during the increase, the system is not in thermal equilibrium; but eventually the system will settle to a uniform temperature. In a system prepared as a block of ice floating in a bath of hot water, and then isolated, the ice can melt; during the melting, the system is not in thermal equilibrium; but eventually its temperature will become uniform. Such changes in isolated systems are irreversible in the sense that while such a change will occur spontanteously whenever the system is prepared in the same way, the reverse change will never occur spontanteously within the isolated system; this is a large part of the content of the second law of thermodynamics. Truly isolated systems hardly occur in nature, and nearly always are artificially prepared.
Read more about this topic: Thermal Equilibrium
Famous quotes containing the words change, internal, state, isolated and/or system:
“Ever since surgery began, mans destiny has been to suffer, in order that he might be cured. And no one can change that, gentlemen.”
—Jean Scott Rogers. Robert Day. Mr. Blount (Frank Pettingell)
“The internal effects of a mutable policy ... poisons the blessings of liberty itself.”
—James Madison (17511836)
“till disproportiond sin
Jarrd against natures chime, and with harsh din
Broke the fair musick that all creatures made
To their great Lord, whose love their motion swayd
In perfect Diapason, whilst they stood
In first obedience, and their state of good.”
—John Milton (16081674)
“I cant earn my own living. I could never make anything turn into money. Its like making fires. A careful assortment of paper, shavings, faggots and kindling nicely tipped with pitch will never light for me. I have never been present when a cigarette butt, extinct, thrown into a damp and isolated spot, started a conflagration in the California woods.”
—Margaret Anderson (18861973)
“Each generations job is to question what parents accept on faith, to explore possibilities, and adapt the last generations system of values for a new age.”
—Frank Pittman (20th century)