What the second law of thermodynamics?

Answer 1

The second law of thermodynamics states that mechanical work can be derived from a body only when that body interacts with another at a lower temperature.

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Answer The laws of thermodynamics have been found to have broader application than the field of thermodynamics. The second law can be stated as: The entropy of an isolated system not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium.- Where entropy can be regarded as randomness or 'chaos'. This application of the second law applies to closed systems, and therefore does not apply to systems that exchange information or energy outside the system. It does not apply to living organisms, as they are not closed systems. The second law applies to macroscopic systems, and therefore does not always apply to microscopic particles. In the field of thermodynamics, it can be stated from the above that the entropy of a thermally isolated macroscopic system never decreases.

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The second law of thermodynamics is:

No process is possible whose sole result is the transfer of heat from a body of lower temperature to a body of higher temperature.

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From the pre-merge Expert answer by Hilmar Zonneveld... Confidence votes 60.8K There are many different ways the Second Law can be expressed, all of them equivalent. Here are some:

* Useful energy can be converted to unusable energy - not the other way round.

* In a closed system, a property called "entropy" can only increase over time - it can never decrease.

* The efficiency of a heat engine can never be greater than that of the theoretical Carnot engine.