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On 03/26/2015 07:28 AM, Bill Norwood wrote:
Might as well open this one up for critique:
Earth is a better perpetual motion machine than anything on it could ever
be, say, relative to a human lifetime.
The critique is this: That's just word games.
The term "perpetual motion" in this context is
an /idiomatic expression/. That is to say, you
cannot infer its meaning based on the separate
words "motion" and "perpetual". Just because
something is in motion, perpetually, does not
make it a perpetual motion machine.
As another example in the word-games category,
consider an oxygen atom, or perhaps one of the
electrons in an oxygen atom. It is perpetually
in motion, and will outlive even the earth.
==========
If we want to do physics, as opposed to word
games:
A perpetual motion machine of the first kind
violates the first law of thermodynamics i.e.
local conservation of energy.
A perpetual motion machine of the second kind
violates the second law of thermodynamics i.e.
local paraconservation of entropy.
The earth is not either of these things.
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