In a room there are two completely identical metal balls. One is lying on a table and the other is hanging on a cable attached to the ceiling.
At the same moment, 1 Joule of heat energy is applied to each of them. Immediately after that, the balls are perfectly insulated, such that absolutely no heat transfer is possible.
Which one is the coldest?
(In reply to
re(2): Just a question + To Ajosin by ajosin)
And if anyone is wondering, no, you cannot cool yourself down by climing up some stairs!.
The reason is that the energy you use to climb the stairs is stored as
quemical energy. The body is not 100% efficient either, so you use more
quemical energy than you really need and you warm up. That is why you
will start sweating if you climb a bunch of stairs.
On the other hand, the metal ball is extremely simple compared to the
body. The ball can only draw energy from the kinetic energy of it's
atoms, so it cools down when it expands up against the gravity field.
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Posted by ajosin
on 2005-04-14 14:01:54 |