Everything posted by exchemist
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Jumping to Conclusions
Yes exactly. In fact one reason I hang out in these places in my retirement is to repoint the brickwork and replace loose roof tiles.
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Jumping to Conclusions
I think it is disconcerting to find that something you thought you knew is wrong, especially when it relates to a subject area that you regard as your citadel of knowledge, i.e. helps to define your self-image. I'm now old enough to tread increasingly carefully, even there, as I'm finding a false memories sometimes catching me out. This is a phenomenon I expect to become more pronounced in the years to come. But taking exposure of error or ignorance as a deliberate attempt to belittle is something else. Normally I think most of us can tell whether someone is just correcting us or whether they are using it as an excuse to indulge in patronising or point-scoring. But perhaps some are over-sensitive and imagine negative motives when there are none.
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Heat Flow
This reminds me of Spike Milligan:" Hey, who turned on the dark?" You get into trouble with the idea of "coldness" when you have to deal with absolute zero. You can't make something as cold as you like, whereas you can make something as hot as you like. So there's an asymmetry there. Just as, with light, you can make something as bright as you like but you can't make it as dark as you like.
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Does eating eggs increase cholesterol? What are the latest scientific studies/data suggesting?
Understood: caveat noted.
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English in science
Actually I think that change served a deliberate purpose. Given that the model of the atom changed radically from the Rutherford-Bohr model to the modern (Schrödinger?) model, the word "orbit" became objectively wrong, so orbital was chosen instead, to signify the new model. P.S. Another name change in chemistry that bamboozled me briefly is from ESR, which I remember from university, to EPR, which is virtually the same thing. I suppose there is in principle a change, in that EPR implies one thinks in terms of the more general J, rather than S.
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Numbering Posts
Yeah but it is handy, in a long thread that is being sensibly discussed, to be able to refer readers back to specific earlier posts. This is the only forum I've been on where the posts are not numbered.
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Does eating eggs increase cholesterol? What are the latest scientific studies/data suggesting?
Indeed. But with oil, which is used for cooking and to dress salads etc, one can reduce it a little without adding anything to replace it. I had been thinking that plenty of it was a good thing, because of HDL. So I can cut it back to just what is necessary. (I don't have a problem with my weight, which has been stable for years at: 66 +/-1 kg and 1.76m in height.)
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Numbering Posts
Agreed. I think this would be very helpful. It seems to be available on other forums.
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According to mainstream physics: Is heat "destroyed" in a heat engine?
Yes, Carnot applied the concept of caloric in that way in his analysis of heat engines. And got it essentially right.
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According to mainstream physics: Is heat "destroyed" in a heat engine?
It wasn't his theory, though. It was Lavoisier's, which Carnot inherited as the then prevailing model and which he suspected was faulty, as some of your earlier extracts from his Appendix A showed.
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According to mainstream physics: Is heat "destroyed" in a heat engine?
Chaleur shurely? 😄 Chauler is a verb, meaning to lime or whitewash. Here is a link to Carnot's original: http://www.numdam.org/item/10.24033/asens.88.pdf Chaleur just means heat and, so far as I can see, will have long predated Lavoisier''s scientific concept of caloric. Lavoiser seems to have introduced caloric because he realised the idea of phlogiston didn't work.
- "The Balloon !"
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English in science
Not interesting ones perhaps, but chemistry is always undergoing revisions to terminology. What used to be carbonium ions when I was at university are now carbocations. The numbering of groups in the Periodic Table has changed. Lots of little things like that. But it was ever thus. I remember my grandfather teasing me, when I was studying for A Level, that I did not even know what muriate of potash was. It turned out to be potassium chloride, KCl, - muriatic acid being an Edwardian-era name for hydrochloric acid (my Grandfather had been born in 1901!). But as for trying to build significance into a particular word translated from early c.19th French, that strikes me as a real fool's errand.
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Heat received from the sun
OK, if you are just calculating radiation intensity, your numbers look good to me. (I used these NASA distance numbers.https://www.jpl.nasa.gov/edu/pdfs/scaless_reference.pdf )
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"The Balloon !"
That old walrus again? I thought he had disappeared along with the Project for the New American Century. (What a laugh that has turned out be.)
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According to mainstream physics: Is heat "destroyed" in a heat engine?
Agreed. However the trouble with cranks, as some of us know to our cost from previous encounters, is that getting us to accept strange and potentially misleading terminology is quite often a rhetorical ruse to promote their crank ideas. In this case it is likely to be, in some way yet to be disclosed, his notion that the Second Law of Thermodynamics is false or can be broken. (This individual has spent over a decade, off and on, on various forums, obsessing about this.) This is why we are wary of agreeing with his peculiar statement without qualifying it. We would not be nearly so cautious if the poster had a track record of posting in good faith.
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Heat received from the sun
It's not clear what you have done. Are those diameter measurements?
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Does eating eggs increase cholesterol? What are the latest scientific studies/data suggesting?
I can still cycle to Wimbledon and back, up and down the hills, to buy bread, as I did before I went on statins, so I'm not worried about muscle weakness. And don't worry, I like olive oil too much to cut it back a great deal.
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According to mainstream physics: Is heat "destroyed" in a heat engine?
Except that the quantity of heat that produced the ΔT cannot be all transformed into work, only part of it.
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According to mainstream physics: Is heat "destroyed" in a heat engine?
But you don't understand: confusion is the object of the exercise. 😄
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According to mainstream physics: Is heat "destroyed" in a heat engine?
None of this quibbling about words gets us anywhere. In the particular case of Carnot, you are reading a translation from early c.19th French. Assuming the original of "destroyed" was "détruit", that could be translated as destroyed, demolished, done away with, effaced, suppressed.... The idea is that (some of) the heat has gone and is no longer there. This is true, it has gone - into work.
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"The Balloon !"
Could be worth considering the territories it passed over on its way. Taiwan? Japan? N/S Korea? Perhaps there could have been other motives besides spying on the USA.
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According to mainstream physics: Is heat "destroyed" in a heat engine?
It is a reference to my metaphor, in your previous thread, for your behaviour on this forum. I said you were trying to playing the victim while wandering about with a huge "Kick me" sign strapped to your arse. And that that is why you get kicked, by me and others. Now perhaps, in turn, you can enlighten us as to why you are so preoccupied with the precise word one uses to describe the conversion of heat into work. (I note that you have not been able to turn up a reference to heat being "destroyed" or "destroyed utterly", and I bet that is not for want of trying.)
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According to mainstream physics: Is heat "destroyed" in a heat engine?
"Destroyed utterly" is a misleading phrase, as it suggests the heat vanishes without trace which, of course, does not happen. Energy, being conserved, is converted into other forms of energy. It is never destroyed. In this case some of the internal energy in heat has been converted into work. So yes, the total amount of heat has been reduced. Your question is such a basic one, and your choice of terms so peculiar, that I can only assume this is a disingenuous question on your part, preparing the ground for another chapter of your stubborn - and increasingly tedious - crankery (KICK 😁).
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"The Balloon !"
Haha. However I don't think this general quite meant that. I think he was trying to stop being dragged into speculation by the line of questioning of a reporter and tried to close it down by saying he would not rule anything out until he had the intelligence reports. Unfortunately that included not ruling out little green men. So now everyone has jumped - either stupidly or disingenuously - on that, to claim "Aha, he thinks it could be little green men!"