Thermodynamics
History
The first established principle of thermodynamics (which eventually became the Second Law) was formulated by Sadi Carnot in 1824. By 1860, as found in the works of those such as Rudolf Clausius and William Thomson, there were two established "principles" of thermodynamics, the first principle and the second principle. As the years passed, these principles turned into "laws." By 1873, for example, thermodynamicist Josiah Willard Gibbs, in his “Graphical Methods in the Thermodynamics of Fluids”, clearly stated that there were two absolute laws of thermodynamics, a first law and a second law.
Over the last 80 years or so, occasionally, various writers have suggested adding Laws, but none of them have been widely accepted.
[edit] Overview
* Zeroth law of thermodynamics
A \sim B \wedge B \sim C \Rightarrow A \sim C
* First law of thermodynamics
\mathrm{d}U=\delta Q-\delta W\,
* Second law of thermodynamics
\oint \frac{\delta Q}{T} \ge 0
* Third law of thermodynamics
T \rightarrow 0, S \rightarrow C
* Onsager reciprocal relations - sometimes called the Fourth Law of Thermodynamics
\mathbf{J}_{u} = L_{uu}\, \nabla(1/T) - L_{ur}\, \nabla(m/T) \!; \mathbf{J}_{r} = L_{ru}\, \nabla(1/T) - L_{rr}\, \nabla(m/T) \!.
[edit] Zeroth law
Main article: Zeroth law of thermodynamics
If two thermodynamic systems are each in thermal equilibrium with a third, then they are in thermal equilibrium with each other.
When two systems are put in contact with each other, there will be a net exchange of energy between them unless or until they are in thermal equilibrium, that is, they contain the same amount of thermal energy for a given volume (say, 1 cubic centimeter, or 1 cubic inch.) While this is a fundamental concept of thermodynamics, the need to state it explicitly as a law was not perceived until
The first established principle of thermodynamics (which eventually became the Second Law) was formulated by Sadi Carnot in 1824. By 1860, as found in the works of those such as Rudolf Clausius and William Thomson, there were two established "principles" of thermodynamics, the first principle and the second principle. As the years passed, these principles turned into "laws." By 1873, for example, thermodynamicist Josiah Willard Gibbs, in his “Graphical Methods in the Thermodynamics of Fluids”, clearly stated that there were two absolute laws of thermodynamics, a first law and a second law.
Over the last 80 years or so, occasionally, various writers have suggested adding Laws, but none of them have been widely accepted.
[edit] Overview
* Zeroth law of thermodynamics
A \sim B \wedge B \sim C \Rightarrow A \sim C
* First law of thermodynamics
\mathrm{d}U=\delta Q-\delta W\,
* Second law of thermodynamics
\oint \frac{\delta Q}{T} \ge 0
* Third law of thermodynamics
T \rightarrow 0, S \rightarrow C
* Onsager reciprocal relations - sometimes called the Fourth Law of Thermodynamics
\mathbf{J}_{u} = L_{uu}\, \nabla(1/T) - L_{ur}\, \nabla(m/T) \!; \mathbf{J}_{r} = L_{ru}\, \nabla(1/T) - L_{rr}\, \nabla(m/T) \!.
[edit] Zeroth law
Main article: Zeroth law of thermodynamics
If two thermodynamic systems are each in thermal equilibrium with a third, then they are in thermal equilibrium with each other.
When two systems are put in contact with each other, there will be a net exchange of energy between them unless or until they are in thermal equilibrium, that is, they contain the same amount of thermal energy for a given volume (say, 1 cubic centimeter, or 1 cubic inch.) While this is a fundamental concept of thermodynamics, the need to state it explicitly as a law was not perceived until