Energy Generation and Flow
This is ultimately limited by some basic physics, some of which
we understand (Thermodyanmics) and some of which we don't (Chaos).
Even though a system may appear to be very simple, the behavior
of that system might be chaotic. The elements of this theory
are hard to describe but some neutrally buoyant helium balloons
floating around class today can serve as an example.
In Class Chaos Demo
Helium balloons and a demonstration of the principles of chaos:
- Unstable equilibrium (a perturbation in either direction
causes an irrecoverable situation)
- No predicative power, our neutrally buoyant helium ballon can
go in any direction
- Random interactions will occur that would not otherwise occur
(e.g. whose head is this balloon going to fall on).
- These random interactions will increase the chaos of the
system (student x bats balloon in some direction).
- An external event which is not in the interactions reduces
the chaos (e.g. the helium runs out and the balloon falls on the floor).
- The nature of the chaotic system is continuously changing -->
i.e. its difficult to maintain the neutral buoyancy of the balloon.
When its not neutrally buoyant, its less chaotic and more deterministic.
- In principle, the motions of the ballon are entirely governed
by physics, hence if we knew all the physics we would have predictive
power. However, the amount of information which is required to be
known is nearly infinite.
So even though the helium balloon is a simple system, its motion and
its interaction with other elements is chaotic.
Chaos seems to exist in a variety of natural systems to some extent
- The Flow of the McKenzie River
- The Greenhouse effect
- Hurricane evolution
- Planetary orbits
- Evolution of species
You can not subvert or change these laws:
The Zeroth Law (0): Systems are in equilibrium when they are at
the same temperature.
- System is in it lowest energy state
- No more energy can be extracted from it
- All systems of different temperature will tend to equilibrium
when they are no longer thermally isolated.
Modelling Thermodynamic Equilibrium:
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The First Law (1): Energy is Conserved in a closed system:
- The net flow of energy across some system is equal to the
change in energy of that system
- We usually consider work and heat flow as the two kinds of
The Second Law (2): The Law of Entropy:
To decrease local entropy requires work (energy).
- Your dorm room - it takes a lot of work to decrease
the amount of disorder
- Iron Ore is originally concentrated in mountains - has a low
disorder. Eventually it becomes mined and ends up distributed in
the nations landfills.
- This combination of letters is readable and hence of low order
and would require a lot of work to rearrange into the previous
- Rich fossil fuel deposits are stored in a state of low order.
when we liberate all of that so that the individual atoms become randomly
distributed, where will society find the energy to maintain
Second Law applied to Power Plants
More on Thermodynamics
of the Second Law
More on the Second Law
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