Thermodynamics Energy flows

Law 0: Equilibrium When two systems are put in contact with each other, there will be a net exchange of energy between them unless or until they are in thermal equilibrium. Energy flows back and forth from one thing to another. This energy flow may take many forms.

Law 1: energy cannot be created or destroyed “In any process, the total energy of the universe remains constant.” All energy in a system comes from somewhere and goes somewhere.

Law 2: Entropy Energy systems have a tendency to increase their entropy rather than decrease it Entropy is heat content. Systems are always leaking energy. Systems are not 100% efficient.

Law 3: One System “As temperature approaches absolute zero, the entropy of a system approaches a constant.” There is no way for a system to have no energy (stillness) because the whole universe is an open system.

Sankey Diagrams

Law 4? Maximum power in living organisms.   Organisms and the earth as a whole have energy budgets; the more efficient we are the more likely we are to survive

Simulation: http://phet.colorado.edu/en/simulation/energy-skate-park-basics This simulation is incorrect: why?