Clausius theorem
E303521
The Clausius theorem is a fundamental result in thermodynamics that formalizes the second law by relating the cyclic integral of heat transfer over temperature to entropy, showing that this quantity is always less than or equal to zero for any cyclic process.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Clausius inequality | 3 |
| Clausius theorem canonical | 1 |
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
result in classical thermodynamics
ⓘ
thermodynamic theorem ⓘ |
| appliesTo | cyclic thermodynamic processes ⓘ |
| assumes |
macroscopic equilibrium states
ⓘ
quasi-static reversible paths for equality case ⓘ |
| concernsQuantity | cyclic integral of δQ/T ⓘ |
| consequence | entropy increase in spontaneous processes ⓘ |
| distinguishes |
irreversible processes
ⓘ
reversible processes ⓘ |
| domainOfValidity | macroscopic thermodynamic systems ⓘ |
| equalityCondition | reversible cyclic process ⓘ |
| field | physics ⓘ |
| formalizes | second law of thermodynamics ⓘ |
| framework | classical thermodynamics ⓘ |
| historicalPeriod | 19th century ⓘ |
| implies |
entropy is a state function
ⓘ
entropy of isolated system does not decrease ⓘ existence of entropy state function ⓘ |
| inequalityDirection | less than or equal to zero ⓘ |
| involves | cyclic integral over closed path in state space ⓘ |
| isFormulationOf |
Clausius statement of the second law of thermodynamics
ⓘ
surface form:
Clausius statement of the second law
|
| mathematicalForm | ∮ (δQ_rev/T) = 0 for reversible cycles ⓘ |
| mathematicalNature | integral inequality ⓘ |
| namedAfter | Rudolf Clausius ⓘ |
| relatedConcept |
Carnot cycle
ⓘ
Kelvin–Planck statement of the second law ⓘ entropy production ⓘ thermodynamic reversibility ⓘ |
| relates |
entropy
ⓘ
heat transfer ⓘ temperature ⓘ |
| shows |
δQ is not an exact differential
ⓘ
δQ/T is an exact differential for reversible processes ⓘ |
| statesInequality | ∮ δQ/T ≤ 0 ⓘ |
| strictInequalityCondition | irreversible cyclic process ⓘ |
| subfield | thermodynamics ⓘ |
| supports |
Clausius theorem
self-linksurface differs
ⓘ
surface form:
Clausius inequality
|
| usedFor | defining integrating factor 1/T for heat ⓘ |
| usedIn |
analysis of heat engine cycles
ⓘ
analysis of refrigeration cycles ⓘ derivation of entropy for general thermodynamic systems ⓘ derivation of entropy for ideal gases ⓘ proofs of maximum efficiency of heat engines ⓘ |
| usedToDefine | entropy change ⓘ |
| usesSymbol |
T
ⓘ
δQ ⓘ ∮ ⓘ |
| validFor | any cyclic process ⓘ |
Referenced by (4)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Clausius inequality
this entity surface form:
Clausius inequality
this entity surface form:
Clausius inequality