Entropy of isolated systems never decreases
Second law of thermodynamics
Entropy of isolated systems never decreases
The second law of thermodynamics establishes entropy as a physical property of a thermodynamic system. It predicts whether processes are forbidden despite obeying the first law of thermodynamics and provides criteria for spontaneous processes. For instance, while the first law allows a cup to fall and break, the second law denies the reverse process of fragments spontaneously reassembling.
Example
Consider a cup falling off a table and breaking. The first law of thermodynamics allows this process. However, the second law of thermodynamics states that the entropy of the isolated system (the cup and the table) never decreases, meaning the fragments cannot spontaneously come back together and jump onto the table.
Remember this
Understanding this principle is crucial for predicting the direction of natural processes and understanding the limitations of energy conversion systems.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
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