First Law of Themodynamics

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Permalink Reply by Tom Delconte on July 30, 2012 at 9:11am

Yes, Jim, you are right, we mostly deal with the first law using classical thermo. It's still correct.

It's statistical thermo that deals with quantum states of atoms and particles. String theory and multiple universes are still under debate. A quark is just a sub-atomic particle which makes up matter. We do deal with deep energy retrofits using the first law of thermo, however, the search for dark energy in the universe has little to do with our daily tasks.

There is an area where advanced physics comes into play within the work of home energy pros: photovoltaics. Solar cells use sunlight as a radiation source to  induce electrons to transfer between different bands (i.e., from the valence to conduction bands) within the material, resulting in the buildup of voltage between two electrodes.

Also some of the electronic components we use like transistors, integrated circuits, diodes, make use of quantum physics and electrodynamics.

 

The laws of thermodyamics still hold in regards to heat, energy, and work in the real world in which we live. From wikipedia:    [sorry, can't get rid of bold type]

The four laws of thermodynamics are:

• Zeroth law of thermodynamics: If two systems are in thermal equilibrium with a third system, they must be in thermal equilibrium with each other. This law helps define the notion of temperature.

• First law of thermodynamics: Heat and work are forms of energy transfer. Energy is invariably conserved but the internal energy of a closed system changes as heat and work are transferred in or out of it. Equivalently, perpetual motion machines of the first kindare impossible.

• Second law of thermodynamics: The entropy of any isolated system not in thermal equilibrium almost always increases.Isolated systems spontaneously evolve towards thermal equilibrium -- the state of maximum entropy of the system -- in a process known as "thermalization". Equivalently, perpetual motion machines of the second kind are impossible.

• Third law of thermodynamics: The entropy of a system approaches a constant value as the temperature approaches zero.The entropy of a system at absolute zero is typically zero, and in all cases is determined only by the number of different ground states it has. Specifically, the entropy of a pure crystalline substance at absolute zero temperature is zero.

Hope this is helpful!

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Permalink Reply by Tom Delconte on August 8, 2012 at 8:13am

Jim, on second thought: Uh oh: entangled particles break second law of thermodynamics . The second law of thermo, or no perpetual motion machines, is being revisited. Quantum teleportation of light particles of 89 miles happened this year: Quantum teleportation using active feed-forward between two Canary ... . There will certainly be quantum technologies introduced into society and home energy applications within the next century. Great discussion topic!

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Permalink Reply by Ed Voytovich on August 9, 2012 at 12:15pm

Jim . . . I would add that plenty of things at the quantum level behave differently than what we are used to observing (and understanding) on the larger scale.   As an example, You might be interested in this video:   http://www.youtube.com/watch?v=DfPeprQ7oGc.

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