|
Water falling from a dam, if it is channeled into canals to produce electricity or to rotate a mill wheel, won't be able to perform labor once it reaches the bottom of the valley. The energy given to that water was used to produce power or to rotate the mill wheel. (30:5) Every time a certain quantity of energy is depleted, it is no longer available and is called "dispersed energy". A rise of entropy, then, means a decrease of available energy. (30:6) In summary: the first law of thermodynamics says that the total quantity of energy and of matter is fixed and it cannot be created or destroyed but only transformed; the second law of thermodynamics says that energy and matter can be transformed only in one direction, from an available state to a non available state or better still from a usable state to a non usable state.
(30:7)
|