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Second Law of Thermodynamics

Physics

The second law of thermodynamics holds that heat does not pass spontaneously from a colder body to a hotter one, and that the entropy of an isolated system never decreases: it increases in any real process and stays constant only in an idealized reversible one. It sets a fundamental limit on how much heat can be converted into useful work and explains why every real energy transformation wastes some energy as unusable heat.

Facts
Proposed Year
1850 1
Clausius's statement; Thomson's independent statement followed in 1851.
Proposed By
Formulated independently in the mid nineteenth century by Rudolf Clausius, who stated it in terms of heat flow, and William Thomson, Lord Kelvin, who stated it in terms of the impossibility of converting heat completely into work; the two statements were soon shown to be equivalent. 1
Connections

Belongs To

Source Second Law of Thermodynamics (Britannica)

Proposed By

Source Rudolf Clausius (Britannica)
Source William Thomson, Baron Kelvin (Britannica)
Sources
1. Second Law of Thermodynamics (Britannica)
Encyclopaedia Britannica
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