1. Thermodynamics
Part 2
The Second Law

2. The 2nd law of thermodynamics
All cyclical processes must expel heat to function. Thus no engines are 100% efficient. (copy Formulae)

3. “The Entropy of the Universe increases in all natural processes”
Entropy is a measure of a system’s disorder.
The more chaotic a system is the higher its entropy.
The Second Law of Thermodynamics is best stated:
“The Entropy of the Universe increases in all natural processes”
Thus a system’s entropy can only decrease if work is done or heat is transferred so that elsewhere entropy increased even more.
so:
Heat flows naturally from Hot to Cold
Heat Engines can’t be 100% efficient