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:
“Wisdom is not just knowing fundamental truths, if these are unconnected with the guidance of life or with a perspective on its meaning. If the deep truths physicists describe about the origin and functioning of the universe have little practical import and do not change our picture of the meaning of the universe and our place within it, then knowing them would not count as wisdom.”
—Robert Nozick (b. 1938)
“The burning of rebellious thoughts in the little breast, of internal hatred and opposition, could not long go on without slight whiffs of external smoke, such as mark the course of subterranean fire.”
—Harriet Beecher Stowe (1811–1896)
“The state is suffering from two opposite vices, avarice and luxury; two plagues which, in the past, have been the ruin of every great empire.”
—Titus Livius (Livy)
“Literature is not exhaustible, for the sufficient and simple reason that a single book is not. A book is not an isolated entity: it is a narration, an axis of innumerable narrations. One literature differs from another, either before or after it, not so much because of the text as for the manner in which it is read.”
—Jorge Luis Borges (1899–1986)
“The intellect is vagabond, and our system of education fosters restlessness. Our minds travel when our bodies are forced to stay at home. We imitate; and what is imitation but the travelling of the mind?”
—Ralph Waldo Emerson (1803–1882)