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And now for something completely different

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Thu Nov 23, 2006 8:16 pm PostPost subject: And now for something completely different
avid_engineer
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I've just thought of something quite interesting.

Steorn claim to be able to create energy by rotating in one direction around a magnetic field, and also to loose energy by rotating in the other direction. An unexplainable loss in energy could potentially be almost as usefull as the gaining. Couldn't this idea of removing energy be used in systems where for example, excess heat is a problem. I'm not talking about refrigeration, but 'destroying' excess heat.

See here for a related thread...

http://fizzx.com/viewtopic.php?t=92

In effect this would also be a self-enforced conervation of energy of sorts, producing energy where it is required and then destroying it where it is in excess. Not that this should promote inefficient mechanical design of course Smile

I am unsure where this idea is leading me, or how it could be systematically achieved but we have been converting various forms of energy to and from heat for millennia so i would guess this is possible.

...or maybe all this waiting around is weirding me out a bit. lol.


Last edited by avid_engineer on Thu Nov 23, 2006 9:44 pm; edited 1 time in total
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Thu Nov 23, 2006 9:42 pm PostPost subject:
WhiteLite
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I'm not sure if it would work so well as you'd have to turn the heat into mechanical energy before you fed it into the machine. Mind you, if this effect is real, there's always the exciting prospect that this technique could be replicated at a molecular level, i.e. you could make molecules that oscilate like the device but reduce the vibration of the atoms that make it which would mean a perpetually cooled substance.

A more conventional idea for the device running in reverse is for braking applications. Currently brakes work via friction and give off a lot of heat, so much heat sometimes that they start to degrade. You only have to look at the ceramic brakes of Formula 1 cars to see how hot they get, they actually glow orange. Using the device in reverse you would have braking without the heat.
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Thu Nov 23, 2006 9:52 pm PostPost subject:
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Yes, that would indeed seem a more practical use. Perhap's when a better understanding of the phenomena is achieved, we could use the principles in a wider variety of ways.

If it is possible to destroy unwanted energy, imagine utilizing a form of this technology on the space shuttle to prevent heat damage to the shielding during re-entry. Absurd i know, and far from Steorn's claims. But with COE down the drain these are the things which could become possible, complete control of energy in the environment.

Of course we have yet to see COE disproven i guess Smile

/me snaps back to reality.
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Fri Nov 24, 2006 1:45 pm PostPost subject:
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That is a very nice idea.
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Mon May 07, 2007 10:18 pm PostPost subject:
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Well, today's my day to bump up some of these old threads.

The important thing to remember is that heat engines of all kinds run on heat _differences_ or flows, not absolute temperatures. For example, take the simple Stirling cycle engine, with which I am sure we all are familiar. If one were truly able to "destroy" energy, then this process would function as the elusive "universal infinite-capacity heat sink", the energy to run our engines would come from the environment, some would be extracted by the Stirling cycle (or any other Carnot heat engine), and disappear into the sixteenth dimension (or wherever). Thus the ability to destroy energy is just as significant (and just as impossible, by the way) as the ability to create it, as far as powering a device is concerned.
It is truly amazing to see a Low-Temp-Differential Stirling engine running while sitting on a bowl of ice, no power source evident--mystifying if one doesn't understand what's going on.
It's running on the flow of heat from the relatively warm room air, into the melting ice. The kinetic energy extracted by the engine is a miniscule amount of the total energy flow, but the engine will continue to run as long as a suitable temperature differential can be maintained.
Have it run the "energy-destroyer" and presto, you've attained Nirvana, found the Holy Grail, created the Philosopher's Stone, put BigOil out of business...but beware the MIBs, they know all about you and are coming for your prototypes and lab notes....
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Tue May 08, 2007 8:29 am PostPost subject:
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Energy and heat are not the same thing. Basic physics. Go learn!
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Tue May 08, 2007 1:02 pm PostPost subject:
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@avid_engineer

I can certainly use a good portable HVAC unit when I'm in Mexico.

What about super-cooling apps?
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Tue May 08, 2007 4:24 pm PostPost subject:
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exco wrote:
Energy and heat are not the same thing. Basic physics. Go learn!


Yep, I learned me up a whole bunch of physics and thermodynamics, and I reckon I understand the differences between energy, power, entropy, work, temperature, and heat, at least well enough for "government work" as we used to say. Razz
Still, loosely speaking, Stirling engines do "run on heat"...and an energy destroyer could be used as a refrigeration system, just as an energy creator could be used as a heater. But as exco pointed out in another thread, this is really underestimating the virtually limitless utility of such a device.

Now, if I could just get the lid off my old jar of phlogiston... Wink
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Tue May 08, 2007 5:01 pm PostPost subject:
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Well, just to check I dug out my sophomore thermodynamics text, just to be sure, and this is what I found:

From "Fundamentals of Classical Thermodynamics" by Van Wylan and Sonntag (1973, John Wiley and Sons) p. 80-81:

"Heat is defined as the form of energy that is transferred across the
boundary of a system at a given temperature to another system (or the surroundings) at a lower temperature by virtue of the temperature difference between the two systems. That is, heat is transferred from the system at the higher to the system at the lower temperature, and the heat transfer occurs solely because of the temperature difference between the two systems. Another aspect of this definition of heat is that a body never contains heat. Rather heat can be identified only as it crosses the boundary. Thus, heat is a transient phenomenon. "

A bit further on:
"It should also be noted that in our sign convention, +Q represents heat transferred to the system, and thus energy is added to the system, and +W represents work done by the system and thus represents energy leaving the system."

There is some more stuff about heat being a path function, thus an inexact differential, and some calculus which I will omit here. (I wish I could have omitted it then, too, but that's another story.)

And from the Van Nostrand's Scientific Encyclopedia (Fifth Edition) p.1245:
(At the end of a long entry on Heat):

"As a result of experiments such as these and a host of others, we are forced to recognize that heat is merely another form of the universal quantity _energy_. Its transformation always occurs at the rate of 4.185 joules per calorie whether heat goes into external work or work is dissipated through friction into heat." (Emphasis in the original.)
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Wed May 09, 2007 4:53 am PostPost subject:
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@WaBoy:
Of course the Stirling cycle can be run "backwards" to give refrigeration too. Just hook up your Orbo to the shaft of the Stirling unit, and use the rotary motion of the Orbo to spin the Stirling. The Orbo will do work on the Stirling's working fluid (I use helium gas in my best ones) by compression and rarefication of the gas; one side of the Stirling will get cold, you can drive a fan off the same shaft to blow air over this cold side into your environmental chamber (a tent?). Use the energy-destroying feature of the Orbo to remove the heat from the Stirling's hot side. Or just stick it outside the tent, if your Orbo is one of the energy-creating ones. What could be simpler? Quiet, too.
Well, at least the Stirling cycle part of this scheme will work--you can use any other motor or engine to drive the Stirling refrigeration cycle until your Orbo is delivered.
Laughing
Remember those tiny air conditioners they used in the 1995 movie version of Michael Crichton's novel "Congo"? I'm sure they worked by Orbo-powered Stirling cycle refrigeration. Great supporting performance by Tim Curry in that movie, btw. Makes me think of earlier, happier days, a very strange movie, Susan Sarandon's wonderful, well... acting, and
"Let's do the Time Warp againnnn...." Mr. Green
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Thu May 10, 2007 9:51 pm PostPost subject:
exco
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I think you'll find stirling engines run, not on heat, but on temperature gradients.

Thus you can make a stirling engine that will run from the heat of your hand, because it is warmer than the surroundings, but the engine would remain stubbornly stalled at a uniform temperature of 200C for instance.
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Fri May 11, 2007 12:30 am PostPost subject:
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exco wrote:
I think you'll find stirling engines run, not on heat, but on temperature gradients.

Thus you can make a stirling engine that will run from the heat of your hand, because it is warmer than the surroundings, but the engine would remain stubbornly stalled at a uniform temperature of 200C for instance.


Of course it would remain stalled, just as you say. But I still maintain that the engine runs on heat, which, as I quoted from the thermodynamics text, is defined thusly:

"Heat is defined as the form of energy that is transferred across the
boundary of a system at a given temperature to another system (or the surroundings) at a lower temperature by virtue of the temperature difference between the two systems. That is, heat is transferred from the system at the higher to the system at the lower temperature, and the heat transfer occurs solely because of the temperature difference between the two systems. "

Which is just what you said.

That's why it is called a "heat engine". Some of the heat being transferred through the engine, due to the temperature difference, is converted to kinetic energy by doing work on the working fluid. And the system's entropy increases.

I don't think we are disagreeing here. But I get confused a lot lately, I will admit that; trying to figure out just what Gaby means will do that to you.

"Another aspect of this definition of heat is that a body never contains heat. Rather heat can be identified only as it crosses the boundary. Thus, heat is a transient phenomenon. "

(reference cited in an earlier post)

So while heat is definitely a form of energy, temperature and heat are not the same thing.
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Fri May 11, 2007 4:02 pm PostPost subject:
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levitation could be another application for absorbing something (gravitiy, what ever this is).

a way this could be done, may be was discussed by american UFO-specialists (Area 51, etc.) Rolling Eyes

As we all know, gravitiy is caused by mass. We also know, there are no natural chemical elements greater than count 104. high elements are not stable. higher elements not found. but some above could be synthesised in reactors.

anti-gravitiy should be possible with shields/generators using elements (114) - 115 - (116). this shall cause a completely antagonistic-field /absorbtion of gravity-field. a wash-out of attraction environmental masses...!????
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Fri May 11, 2007 4:37 pm PostPost subject:
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Idea ..maybe because these (ultra-short-stable and extremely fluctuant) elements are as huge as the "periodic wavelength" of the gravity-quantum-strings (i am phantasizing a bit)
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Fri May 11, 2007 8:05 pm PostPost subject:
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I think things would be a lot clearer if some of the people here talking glibly about 'energy', 'work', 'entropy' and 'power' would take the trouble to clarify the distinction between these - it is REALLLY important - in their heads before leaping into typing idiotic posts.

I suggest any secondary school (high schoool?) physics text book would make the matter crystal clear, and we might make some progress if people didn't play fast and loose with these definitions. It is important because if we disagree on what these measurements are, then any meaningful discourse is impossible. The conventional definitions have served geniuses like newton and einstein well over the years, and I suggest we adhere to them.

Sorry to be so nitpicking, but If I am counting goats, and you are under the impression that they are lemons, then it's pretty unlikely that any real understanding between us can be reached.
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Fri May 11, 2007 8:17 pm PostPost subject:
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A quote:

Another aspect of this definition of heat is that a body never contains heat. Rather heat can be identified only as it crosses the boundary. Thus, heat is a transient phenomenon.

This is nonsense. Heat can be measured by using a thermometer to measure the temperature and multiplying it by the specific heat of material whose temperature you are measuring. The answer is in calories.

If the whole of the universe were at a uniform temperature of - say 1000C, it would contain a vast amount of heat, but no energy extractable by thermodynamic machines.

This is an illustration of how important it is to understand these simple, very basic concepts before any meaningful discussion can occur.

If you ask me, steorn only exists because they are either deliberately or unintentionall taking advantage of people's ignorance of the distinction between these simle well-defined concepts.

For your own peace of mind, I urge anyone confused to go and read up on the subject.
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Sat May 12, 2007 5:40 am PostPost subject:
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There are a number of physics learning resources in the "Physics" section of this site. I'd recommend the "Physics for Future Presidents" UC Berkeley lectures as a starting point. (Available on Google Video)
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Sat May 12, 2007 8:57 am PostPost subject:
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exco wrote:
A quote:

Another aspect of this definition of heat is that a body never contains heat. Rather heat can be identified only as it crosses the boundary. Thus, heat is a transient phenomenon.

This is nonsense. Heat can be measured by using a thermometer to measure the temperature and multiplying it by the specific heat of material whose temperature you are measuring. The answer is in calories.

etc.


I didn't make it up, I gave the reference above, here it is again, this is a standard and well-respected college (usually 2nd or 3rd year) text used in physics and engineering courses.
Of course that doesn't mean it isn't nonsense, but it is what physicists and engineers are taught, and what they use to solve problems.

From "Fundamentals of Classical Thermodynamics" by Van Wylan and Sonntag (1973, John Wiley and Sons) p. 80-81:

"Heat is defined as the form of energy that is transferred across the
boundary of a system at a given temperature to another system (or the surroundings) at a lower temperature by virtue of the temperature difference between the two systems. That is, heat is transferred from the system at the higher to the system at the lower temperature, and the heat transfer occurs solely because of the temperature difference between the two systems. Another aspect of this definition of heat is that a body never contains heat. Rather heat can be identified only as it crosses the boundary. Thus, heat is a transient phenomenon. "

The calculation you describe leaves out several factors. For example, for real gases the specific heat varies with pressure as well as temperature; and surely you will admit that the "heat content" of a material also depends on how much material you've got. The answer is not in calories, but in calories per unit mass. And to beat a dead horse even more, even the concept (and definition) of temperature is not as simple as you seem to make it out. Temperature is defined as "that property of systems which determines whether they are in thermodynamic equilibrium. Two systems are in equilibrium when their temperatures...are equal." (Van Nostrand's Scientific Encyclopedia, 5th ed. pp. 2175-2176. ) Interestingly enough, in this reference an entire (big, two-column) page is given to the definition of "temperature" and yet the words "heat" and "energy" do not appear at all.
Even the value of a "calorie" is not so simple. The energy equivalent of a calorie of heat varies with the temperature! The common conversion of 1 calorie=4.185 Joules is valid only for the standard "15-degree calorie". The specific heat of water varies from about 1.008 calories per gram-degree at 0 degrees C to a low of about 0.998 calories per gram-degree at about 30 degrees C, then climbs again to about 1.007 calories per gram-degree at 100 degrees C. (ibid., p.1245).

I also find it interesting that I can quote solid references for my points, but all I get in response is jargon and innuendo.
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Sat May 12, 2007 2:25 pm PostPost subject:
exco
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Well of course I left the minutiae out. there are many ways you can measure heat. If you have a gas it is proportional to the average velocity of the molecules that compose it, and of course temperature and pressure come into it. You could in principle measure the heat content of- say a block of aluminium by measuring it's density. This is inveresly related to its temperature from which the quantity of heat can be established. If you're worried about my rough and ready calorie definition, then you can give the answer directly in Joules, or even foot pounds.

The point I am making is simple however. Heat is something that a body (or mass of gas) contains which can be readily measured and defined by methods other than looking at transfers to and from the surroundings, which is what your book claims.

The words:

" Rather heat can be identified only as it crosses the boundary"

- is simply wrong. The exercise/experiment I suggested is the proof of this wrongness.

I'm all for books, but not at the expense of reasoning or experimental evidence.
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Sat May 12, 2007 2:31 pm PostPost subject:
exco
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Another pronouncement from the book you quote sticks in my craw too.

"Heat is a transient phenomenon"

Not so. If we take the universe and imagine it when it has completely 'run down' Everything in it is uniformly at the same temperature, that temperature would be about 4 degrees absolute. Cold!

But there is some heat left even at this temperature, and the universe contains a lot of mass. The total amount of heat would be very large, and this state would last for all etermity. It is a far from transient phenomenon.

I'm sorry to be nitpicking, but that's what it's all about.
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Sat May 12, 2007 6:48 pm PostPost subject:
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Gahhh! Here I come trying to agree with you with a reference to give that I think couches things in a way that is more in accord with the way you put them, trying to be friendly, but you have beat me to it with another "silly bomb".
"Engines, Energy, and Entropy" by John B. Fenn , 1986 (New York:Freeman and Co.)
This book basically says that energy is the ability to do work, temperature is a measure of what Fenn calls "internal energy", etc. But even his definition of heat is as follows: "Heat is the interaction (what happens) between a hot object and a cold object that are in contact with each other." (in bold type in the original, on p.5). The chapter subhead here is "Heat and Work are Different."
Later on when describing Joule's experiments he says that Joule proved that heat and work are equivalent (p. 125)! So I think his description is more like: energy is the ability to do work; internal energy is the result of work having been done on a system, which can be observed (sometimes) by a rise in temperature; the definition of work includes the idea of heat crossing a system boundary, etc.
Also in Chapter 5 he says that "heat is a happening".
Note that even this text describes heat as an interaction that occurs at a system boundary.
Fenn tries to deal with these concepts without the use of much calculus, but even he finds it necessary to introduce some partial differential equations when defining temperature, heat, work, entropy, etc.

I must point out, however, that the Van Wylen and Sonntag text that I quote from is a standard major textbook for thermodynamics courses that physics, chemical engineering, and mechanical engineering majors must pass in order to receive an actual university degree in these areas; it is heavily loaded with calculus, actual problem sets, and etc., while the Fenn text is sometimes used in those "Physics for Non-Science Majors" courses that liberal-arts majors usually have to take at decent colleges.

"If a hot object is put in contact with a cold one, the hot object cools off and the cold one warms up. Finally they reach a state of _thermal equilibrium_ in which they both feel equally hot (or cold). We call what happens between the two objects _heat_ , more properly, a _heat interaction_. (Fenn, op.cit. p.15, emphasis in the original.) Note again the appearance of the concept of flow across a boundary in this definition.

I'm not saying that you are incorrect, exactly, just that your understanding seems more in accord with the latter approach than the former.

The problem with the "transient" concept may again be due to a specialised use of the word. The Van Wylen and Sonntag text defines this more accurately using partial differentials and path integrals, and it is a concept necessary for their derivations. But even Fenn agrees here, although he couches it in somewhat different terms, since he tries hard to avoid calculus.

I think if you disagree with the authors of a major thermodynamics text, you should provide some real evidence to support your contentions.

But can't you cite even one reference that supports your points? Please?

(Believe me, that whole VW & S text "stuck in my craw" back then, too, but for different reasons--I actually had to work through the problem sets!)

Rolling Eyes
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Sat May 12, 2007 7:08 pm PostPost subject:
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exco wrote:

The point I am making is simple however. Heat is something that a body (or mass of gas) contains which can be readily measured and defined by methods other than looking at transfers to and from the surroundings, which is what your book claims.


How, then?
(BTW the "book" says "across a system boundary", which is a bit more complicated than "the surroundings".)
If you say "stick a thermometer in it" I will just laugh. The thermometer measures "heat" if you will by virtue of the work done as the thermometer's working fluid comes into equilibrium with the object being measured. That is, a transient event that occurs at a system boundary. Even though the thermometer's scale is in "degrees" of one kind or another, what you are really measuring is work done by virtue of heat transfer. Ditto thermocouples, etc.
In your "constant temperature universes", you would be unable to measure heat, because no thermodynamic work could be done on a measuring instrument, and because no heat could cross any boundaries--everything is in equilibrium.

C'mon, cite a reference for your claims!
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Sat May 12, 2007 7:34 pm PostPost subject:
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Come on! You are just being silly here.

You could paint the thing in liquid crystal paint and measure the temperature from the colour, or you could measure the speed of ultrasonic pulses through it or half a dozen other ways. Your objection to ANY method could be overcome by locating yourself - equipped with a thermometer INSIDE the object being heated. then nothing leaves the system.

What the book is trying to say (I think) is that although heat is a form of energy, you cannot convert it into energy without heat flowing out of the system (or into it)

This is correct, but to say you cannot measure heat without a flow of energy from the system is nonsense. You can make the energy flow arbitrarily small or by getting inside it, eliminate even the tiny amount of energy needed to carry the information from the system.

I don't thinlk you've understood this at all.
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Sat May 12, 2007 7:58 pm PostPost subject:
exco
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I'm not particulary interested in whether the process of measuring temperature requires heat to flow or not. I think this - if true - is a pretty trivial observation, because you can make it as small as you want.

My argument is simply that objects DO contain heat, and in principle it can be measured to whatever degree of accuracy you require (if you have the time, patience and money) Basically you need a thermometer and a knowledge of the specific heat at thet temperature.

Second, I contend that although heat is a form of energy, it is not useable unless you have something cooler or hotter than it, so that a flow of heat can occur.

Heat is NOT a transient phenomenon, despite the fact that it may not be measurable. As I have pointed out the heat-dead universe would undoubtedly contain heat in vast quantities despite the fact that we could neither measure it nor extract energy from it.

I think this is clear enough gedankenexperiment to make any references somewhat superfluous, don't you?
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Sat May 12, 2007 8:37 pm PostPost subject:
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No.
I still maintain that if you disagree with that thermodynamics textbook, and all the other references I cite that include derivations and citations of many many _real_ experiments, you must come up with some citations of your own that support your points. Until you can do that, I will just have to accept what my references say--since, as they say, "I've done the math" (although it was some time ago.)

Now this is not to say that I completely disagree with your major points--I just still think that you are using terms in a more colloquial sense, and I am using more strict scientific definitions, as stated and derived in these texts. By your definition of "transient phenomenon" and your definition of "heat", I almost fully agree with your points. It is just that, using these definitions, you cannot solve many real-world numerical problems concerning heat, work, etc. which can be solved using the more precise definitions as contained in all these damn textbooks.


But what about those endothermic chemical reactions? Do you back up so far as to draw your system boundary at some remote point in time and distance when the sodium hypochlorite crystals were crystallized initially?
Pour some water at 20 degrees C into some "hypo" crystals at 20 degrees C--the solution will get quite a bit colder as you stir it and the hypo dissolves. What happened to your "heat" by your definition? It sure didn't get dumped into some colder external sink, but work has indeed been performed on the system, and it got colder.
This isn't a gedankenexperiment or a straw man--you need real thermodynamics to explain what happens.
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Sat May 12, 2007 9:12 pm PostPost subject:
exco
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I think you'll find that if you simply add heat to hypo rather than water that it will behave in a perfectly rational manner. The more heat you add, the hotter it gets.

I don't know why you introduce these straw men. But if that is the level of argument you want to descend to, I can cheerfully cite sodium, when adding hot water pretty well guarantees a rise in temperature!

You are deliberately raising red herrings.

I am also a little surprised that you choose to give more weight to the opinions of an 'expert' rather than conduct your own thinking and drawing your own conclusions. Believing books uncritically is not my way. If the book makes sense, then I'm happy to accept it, but if it doesn't, then the hell with it. The inmates of steorn will of course encourage you to believe what a panel of experts tell you rather than have you use your commonsense.

I really don't know the context of the passages you quote, namely:

"Another aspect of this definition of heat is that a body never contains heat. Rather heat can be identified only as it crosses the boundary. Thus, heat is a transient phenomenon. "

But as a stand-alone statement it is palpable nonsense. The writer has for his own purposes redefined what heat is. He might just as well redefined it as custard, and defined one of its properties as being yellow.

The fact is that I can fill my thermos flask with hot tea, which clearly contains a given quantity of heat, and several hours later pour out a cup which STILL contains enough heat for an enjoyable cuppa! The heat is neither transitory (within the limits of the flask's insulation) nor dependent on the transfer of heat from tea to lips. Whether I perceive it as hot or not, it is still hot.

If you want me to cite a reference, then this is it. I would also suggest that you maintain a properly scientific scepticism, even for books full of calculus written by experts and to do your own thinking.

I think we're more likely to get somewhere by rational argument than by brandishing tomes at each other, or deliberately muddying the water with irrelevancies like sodium thiosulphate or balloons full of helium.
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Sun May 13, 2007 5:55 am PostPost subject:
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exco -- you may be confusing "heat" with "internal energy". It's a common error that I'm often guilty of making!
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Sun May 13, 2007 12:55 pm PostPost subject:
avid_engineer
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Interesting that these old threads are coming back to life Smile

Just FYI, i wasn't trying to say heat is energy, but it is a common manifestation of excess (redundant) energy in a system. My point was that this viewpoint would offer applications that AFAIK had not been considered so far.
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Sun May 13, 2007 2:01 pm PostPost subject:
exco
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"exco -- you may be confusing "heat" with "internal energy". It's a common error that I'm often guilty of making!"

I'm not confusing anything. You are. Why redefine a perfectly simple concept for no apparent reason?

Everyone is familiar with a hot cuppa, we do not need to redefine it as an 'internal energy rich cuppa'!

I will withdraw my remark if you can exhibit an internally energy rich cuppa that is not a hot cuppa or vice versa.
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Mon May 14, 2007 12:34 am PostPost subject:
alsetalokin
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Thanks for weighing in, drichardson. I was beginning to think I should send my degrees back and sue for all the tuition I paid!

@exco: The reason people cite exact references is to identify the context, for one thing. If you want to challenge the context, crack the book--I even gave you the page number(s) for the quotes. The reason the terms are defined that way is so that real-world problems can be solved, using the concepts, and maths including path integrals. You may not agree, but you can bet the engineers who designed that turbojet engine hanging out there on the wing of an airliner, or the diesel engine powering the generators in your local commuter train, will.

But, finally, I have found a reference that seems to support exco's use of terminology. Here's the quote:
"Let's look at the impact itself. Some of the energy is converted into _sound_. Some goes into distorting the floor--and distorting Ringo, for that matter. And some, even most, goes into _HEAT_. Ringo and the floor are both a little warmer after the collision. The impact jiggles their molecules--and heat is nothing but the kinetic energy of billions of molecules!!!" [emphasis in the original--along with a drawing of a thermometer in contact with the floor].
The reference: "The Cartoon Guide to Physics" by Gonick and Huffman (New York:HarperPerennial), p. 80.

OK, I quit. After all, I think exco and I are actually on the same side, and I'd love to be able to hoist a pint or two of bitter ale down at the local while we prove that a Universe which contains an Orbo can't possibly exist!

Mr. Green
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