2nd Law of Thermodynamics

By ``closed'', we mean a system that is completely cut-off, or insulated from its surroundings, so that no material or energy enters or leaves.

Also as discussed in the last chapter, heat, being a form of energy, can
be transformed into work and
other forms of energy, and vice versa. However, this transformation of heat energy
is subject to a very important restriction, called the
**2nd law of thermodynamics**. This law is in fact necessary to
resolve the following apparent paradox:

The answer lies in the statement of the 2nd law of thermodynamics, which can be given in three equivalent forms:

When phrased in a precise mathematical language, one can show that any one
of the forms of the 2nd law imply the other two.
We shall discuss each of these three forms in turn.

1999-09-29