Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

adiabatic processes

At 11:50 AM -0700 1/6/00, Jim Green wrote:

As an experimentalist, we used the word 'adiabatic' to describe a
PROCESS not a 'wall'.

We were pretty good at 'Adiabatic Demagnetization' as a cooling
method. The vacuum chamber reduced conductive and convective
processes and 'heat shields' were used to reduce radiative transfer
to the cryogenic sample.

I've managed to avoid the dreaded four letter Anglo-Saxonism except
for the 'heat shield' term. I don't know what else to call them. I'm
sure there is some Pedagogically Correct term for these things that
reduced radiative transfer by means of successively lower temperature
baffles.


Should we forbid elementary schools from mentioning
conduction, convection and radiation as important environmental
concepts of today?



I would use the word "adiabatic" as meaning that no "action" can pass
through a "wall" -- usually the work of microscopic collisions of molecules
-- but the point asked about is well taken -- the handle of the propeller
does pass through the wall as do the wires from the battery to the
resistor. So I would now say that _I_ would mean by "adiabatic" that no
microscopic work is done by molecular collisions -- as _can_ be done though
the isothermal window, but that shafts and wires do not compromise the
barrier.

-. .-. .-. .-. .-. .-. .-. .-. .-. .-
\ / \ / \ N / \ C / \ S / \ S / \ M / \ / \ /
`-' `-' `-' `-' `-' `-' `-' `-' `-'
Chuck Britton Education is what is left when
britton@academic.ncssm.edu you have forgotten everything
North Carolina School of Science & Math you learned in school.
(919) 286-3366 x224 Albert Einstein, 1936