Free Energy and Exergy
The amount of useful work which may be extracted from a thermodynamic system is determined by the second law of thermodynamics. Under many practical situations this can be represented by the thermodynamic availability, or Exergy, function. Two important cases are: in thermodynamic systems where the temperature and volume are held constant, the measure of useful work attainable is the Helmholtz free energy function; and in systems where the temperature and pressure are held constant, the measure of useful work attainable is the Gibbs free energy.
Read more about this topic: Work (thermodynamics)
Famous quotes containing the words free and/or energy:
“If we focus mostly on how we might have been partly or wholly to blame for what might have been less than a perfect, problem- free childhood, our guilt will overwhelm their pain. It becomes a story about us, not them. . . . When we listen, accept, and acknowledge, we feel regret instead, which is simply guilt without neurosis.”
—Jane Adams (20th century)
“Because humans are not alone in exhibiting such behavior—bees stockpile royal jelly, birds feather their nests, mice shred paper—it’s possible that a pregnant woman who scrubs her house from floor to ceiling [just before her baby is born] is responding to a biological imperative . . . . Of course there are those who believe that . . . the burst of energy that propels a pregnant woman to clean her house is a perfectly natural response to their mother’s impending visit.”
—Mary Arrigo (20th century)