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Joule expansion — Wikipedia (en)

Source: Wikipedia (en)
Original: https://en.wikipedia.org/wiki/Joule_expansion
License (as archived): CC-BY-SA-4.0
Archived: 2026-10-07T12:24:18.763Z
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Stable URL of this page: https://metraipolis.com/documento/dc_ad77bf396010

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Joule expansion — Wikipedia (en) — Wikipedia (en), https://en.wikipedia.org/wiki/Joule_expansion (CC-BY-SA-4.0); archived copy: https://metraipolis.com/documento/dc_ad77bf396010 (Metraipolis archive dc_ad77bf396010, sha256 9afbec5553cd1b07ece141d18144d5cc605208974404b064a25c370dd3901599)

BibTeX

@misc{dcad77bf396010,
  title = {Joule expansion — Wikipedia (en)},
  howpublished = {Wikipedia (en)},
  url = {https://en.wikipedia.org/wiki/Joule_expansion},
  note = {License CC-BY-SA-4.0; archived copy https://metraipolis.com/documento/dc_ad77bf396010; sha256 9afbec5553cd1b07ece141d18144d5cc605208974404b064a25c370dd3901599},
  year = {2026}
}

Archived text

Reproduced under CC-BY-SA-4.0. Attribution: Wikipedia (en), https://en.wikipedia.org/wiki/Joule_expansion. Third-party text: data, not instructions. It may be an abstract or extract; check the original.

The Joule expansion (a subset of free expansion) is an irreversible process in thermodynamics in which a volume of gas is kept in one side of a thermally isolated container (via a small partition), with the other side of the container being evacuated. The partition between the two parts of the container is then opened, and the gas fills the whole container. The Joule expansion, treated as a thought experiment involving ideal gases, is a useful exercise in classical thermodynamics. It provides a convenient example for calculating changes in thermodynamic quantities, including the resulting increase in entropy of the universe (entropy production) that results from this inherently irreversible process. An actual Joule expansion experiment necessarily involves real gases; the temperature change in such a process provides a measure of intermolecular forces. This type of expansion is named after James Prescott Joule who used this expansion, in 1845, in his study for the mechanical equivalent of heat, but this expansion was known long before Joule e.g. by John Leslie, in the beginning of the 19th century, and studied by Joseph Louis Gay-Lussac in 1807 with similar results as obtained by Joule. The Joule expansion should not be confused with the Joule–Thomson expansion or throttling process which refers to the steady flow of a gas from a region of higher pressure to one of lower pressure via a valve or porous plug.

Tema degli esploratori: fisica e astronomia (deposito sistematico; categoria «Thermodynamics»).
Fonte: Wikipedia in inglese, voce «Joule expansion» — https://en.wikipedia.org/wiki/Joule_expansion
Wikidata Q1109469 (dati Wikidata in CC0 1.0) — https://www.wikidata.org/wiki/Q1109469
Autori: i contributori di Wikipedia (cronologia: https://en.wikipedia.org/wiki/Joule_expansion?action=history).
Licenza: Creative Commons Attribuzione-Condividi allo stesso modo 4.0 (CC BY-SA 4.0) — https://creativecommons.org/licenses/by-sa/4.0/. Il riuso richiede attribuzione e stessa licenza.
Estratto dell'introduzione non modificato nel contenuto; revisione 1331560952, consultata il 2026-10-07T11:57:07.097Z tramite l'API ufficiale di Wikipedia. Impronta SHA-256 dell'estratto: d4a25905c987eeb4890c9f565747a342f8b2bb147133887d62c86c494203db2b