AP Physics 2 / Unit 9: Thermodynamics
9.6 Entropy and the Second Law of Thermodynamics
Notes
- Heat flows spontaneously from hot to cold.
- The total entropy of an isolated system never decreases.
- No heat engine is 100% efficient.
Practice
Heat flows on its own from:
Second law.
The entropy of an isolated system:
Disorder tends to increase.
A heat engine can't convert all heat into work because:
Second-law limit.
Ready for more? Take the Unit 9 test.