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Second law of thermodynamics

For a process, the entropy change of a system is at least the heat added divided by the absolute temperature, with equality only for reversible processes. It states that the entropy of an isolated system never decreases and sets the direction of spontaneous processes.

dS \geq \frac{\delta Q}{T}

What the symbols mean

infinitesimal change in entropy of the system (J/K)
infinitesimal heat added to the system (J)
absolute temperature at which the heat is transferred (K)

About this formula

  • FieldPhysics
  • TopicThermodynamics
  • LevelUniversity
  • Also calledentropy increase law, entropy inequality, clausius inequality, entropy never decreases, second law entropy, irreversibility law

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