[net.physics] Thermal Extravaganza

williams@kirk.DEC (John Williams 223-3402) (05/09/85)

                  Unidirectional Heat Transfer

        If you, let's say, used cold as  a  means  of  integrated
measurement,  you  would  find that cold transfers to hot objects
according to all the same laws that govern heat being transferred
to  cool objects, only reversed.  The heat coordinate analysis is
simply a convenient tool, and is in  actuality  just  a  standard
convention for solving thermodynamic problems.

        Heat is simply  a  means  of  expressing  the  motion  of
molecules,  etc.,  within  a  confined  region.   This  motion is
conserved, but distributed throughout the medium,  statistically,
with  an  exponential  decay.   Some  is  lost,  however,  to the
environment.

        This is not to say that  the  laws  of  conservation  are
invalid,  just  simply  that  conservation  extends  out into the
environment, not necessarily the " closed "  system  you  had  in
mind.   Energy  is  transferred  bidirectionally,  but,  the only
difference you are able to measure is the complete result,  which
statistically  transfers  more energy to the cold object from the
hot object than vice-versa.

                                        John Williams

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