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To: 2AtHomeMom

>>Flak about math fonts, with a little science thrown in which doesn't change the issue:<<

Well here are a few responses to that post which you seem to say you only had a font problem ...

To: 2AtHomeMom
As we all know, delta-S = SdQ/T. (S is entropy, SdQ the energy input, T the absolute temperature.)
Crap. We all know no such thing. Whoever wrote this idiocy - and I suspect it wasn't you; you probably cribbed it from some basher web-site - can't even transcribe a formula correctly, let alone understand it.

The equation is dS=dqrev/T. q (lower case) is the reversible heat, not the energy. Unless you specify it's the reversible heat, it's not correct to write it as a differential at all. Heat itself is a path variable.

While you're staying at home, Mom, pick up a chemistry text.


605 posted on 01/30/2005 2:31:55 PM PST by Right Wing Professor




To: 2AtHomeMom
As we all know, delta-S = SdQ/T. (S is entropy, SdQ the energy input, T the absolute temperature.) On inspection, change of entropy is always nonnegative;
Your equation is for reversible processes where the net entropy is ZERO. Let me quote from a reputable science text for that situation:

"The interpretation of entropy as a measure of the capacity of a system for doing work is consistent with the result that the change in entropy is zero for a reversible cycle, for a system carried through such a cycle loses no capacity for work"

BTW, which YEC website did you get that "T the absolute temperature" quote from?


620 posted on 01/30/2005 2:47:11 PM PST by WildTurkey




3) Pointing out that entropy is 0 is in perfect agreement with my statement that entropy is nonnegative and does not advance WT's case.
I would have thouth you would have said zero since you you left open the posibility of positive entopy change in your statement. Nice try, though. Strike ONE!

And we don't all have math fonts turned on.

Math fonts won't get you from reversible to irreverible cycles. Srike TWO!

I am open to a civil, moderated education on path variables and reversible cycles, please proceed. I suspect reversible cycles apply to open systems, because how could entropy increase over time in a closed system? See you later.

Let me quote from the same previous text:

"These equations (entropy) can be summarized by the statement that a natural process always takes place in such a direction as to cause an increase in the entropy of the system plus environment. In the case of an isolated system it is the entropy of the system that tends to increase."

Strike Three. You are OUT!


1,044 posted on 01/31/2005 8:04:40 PM PST by WildTurkey (When will CBS Retract and Apologize?)
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