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Challenge: Problem 4

"Energy is neither created nor destroyed." Excepting a few cosmological theories, and allowing for the mass-energy equivalence, this statement is as true as any we can hope to formulate in physics. But it tells only about the total quantity of energy, and says nothing about the changes that must take place in the state of energy with transformations. In the middle of the nineteenth century, when the concept of entropy began to evolve, talk arose of the inevitable "heat death" of the universe. Since there is no interaction or process whatsoever in which the total amount of disordering decreases, in time disordering must overcome all forms of structure and organization, so that no dynamic process can then occur.

Now "all life on earth", or the Biosphere, is a complex but limited mechanism that for many thousands of millions of years will be able to both maintain and even increase its level of order, and also engage in the most varied internal processes. Consider how it is able to do this and how in doing so it conforms to the Second Law; that is, how it contributes towards the growing disorder of the solar system and the universe. Think about it for a while, then translate your ideas into a selection of response items so that you and the author can interact in their thinking.

1
heat transfer takes energy from hotter to cooler systems		 2
thermal capacity		 3
isothermal change		 4
a change in volume 		5
transfer of energy by work, involves no change in entropy
6
latent heat		 7
adiabatic change		 8
a change in temperature		 9
internal energy does not consist only of thermal energy		 10
the internal energy periodically returns to its initial magnitude
11
conversion of work into heat production, as in the case of friction		 12
a change in internal energy		 13
absolute temperature-measure of the intensity of thermal energy		 14
internal transition from potential to thermal energy		 15
work output by system
16
a change in entropy		 17
the lower the intensity at which a transfer of energy takes place, the greater the increase of its extension within the system		 18
external stores of thermal energy		 19
changing entropy of a system by heat transfer to a cooler system		 20
the entropy associated with thermal energy at zero intensity