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| quote: | Originally posted by solgrabber
they did? or did they get demolished after exploding inside the towers because of the bombs attached to them and the ones going off inside the building. |
Uh... why would they put bombs in the building AND fly a plane into it? Just how dense are you? If the U.S. government was in on this conspiracy, why wouldn't they forget about the stupid planes and just plant bombs in the WTC?
Are you forgetting that about 6 years earlier, terrorists actually *tried* and failed to bomb the WTC?
| quote: | | honestly to many people are way too ignorant. |
Yes - namely, you.
| quote: | | planes liquifying? lol, why is it on that day all these planes did this but through all the years tons of other plane crashes do not resemble this liquify theory? |
Do you not understand even basic physics? Most of the heat was generated from the burning floors of the WTC, not the plane itself.
There's a whole long-winded discussion of this issue on a Physics forum (click), I'll post two quotes from the guy who put all the conspiracy theorists in their place:
| quote: | Foxx, you have consistently ignored the source of the majority of the heat: the contents of the burning floors. One floor's worth of material, very conservatively estimated, is FOUR TIMES the energy of one third of the available jet fuel; so even if we TOTALLY IGNORE the jet fuel, four-fifths of the energy remains. That energy is FOUR TIMES what is needed to COMPLETELY LIQUIFY the ENTIRE STEEL CONTENT of a floor, and the estimate of the steel content of a floor is probably twice the actual content, because higher floors have less steel, and the floor involved was relatively high on the building.
Not only that, but you said, "That heat is lost to the PE..." indicating that you have made a bad assumption: that the PE of burning I am calculating is part of the gravitational PE of the building. Nothing could be further from the truth. The calculations I made of the gravitational PE of the building DO NOT INCLUDE any of the PE of the burning materials; thus the figures for gravitational PE and burning PE are COMPLETELY SEPARATE and must be added together to get the entire PE, and in addition, the burning jet fuel adds only a very small fraction to the entire PE involved. By far the largest source of energy is the burning contents of the building, in fact, by a factor of TEN OR MORE. You have consistently COMPLETELY IGNORED this energy source, as has every other analysis posted so far.
Even supposing that 75% of the energy of the burning contents of the building on the damaged floors escaped into the surrounding air, there is still MORE THAN ENOUGH TO COMPLETELY LIQUIFY ALL THE STEEL IN A SINGLE FLOOR. And because of the peculiarities of construction (can you say, "viscous dampening?") that means that even if 75% of the heat escaped during the fire, there is still MORE THAN TWICE AS MUCH AS IS NEEDED to compromise the joists and their trusses, and/or the connection plates either between the joists/trusses and the core or perimeter, or between the perimeter column sections. Not only that, but if the heat was escaping to the outside air, a fair bit of it had to pass by the perimeter columns, and if those fail, then there is nothing holding up the outsides of the floors; which then obviously collapse, leading straight back to the original discussion.
And once again, if we start talking about the heat being conducted away, we have the prior discussion of the bar of steel held in the bare hand of the smith, with the other end glowing white-hot. The index of thermal conductivity of steel just isn't that high. And then we discuss viscous damping again, and the fact that viscous dampening means that the floor joists and their trusses were not strongly thermally linked to either the core or the perimeter.
Really, the whole thing is ridiculous and always was; serious consideration of the factors convinced me LONG AGO that there was nothing wrong with the "pancake scenario." But everybody WANTS a conspiracy scenario, with demolition explosives and other stupid crap, so they all try to prove it by ignoring OBVIOUS factors.
This emotional need makes people extremely testy when it is denied, and that makes them quite difficult to get along with; I therefore have begun to approach these "discussions" filled with misconceptions, inaccuracies, misunderstandings, and lack of knowledge of BASIC PHYSICS quite aggressively, because I have already been through the mill and didn't like it the first five times. Challenge me on technical grounds, and you will get a civil and comprehensive answer; more posturing and accusing me of being a shill for this administration (which I absolutely DETEST, by the way- Shrub is without honor, lies at the drop of a hat, and can never be bothered to acknowledge previous lies, and his accomplices are, if anything, worse by far), on the other hand, will do nothing but arouse my fury, and I can be extremely impolite when I am angry. You have been civil so far, please remain that way despite your disappointment.
I suggest a careful, skeptical review of Crossing the Rubicon. You can't take everything Ruppert says at face value- he misses some pretty basic physics, and makes some real mistakes because of it- but you can't fault his research, he's one of the best researchers around. I remain convinced that there was collusion at the highest levels of this administration; I am merely arguing that that collusion did NOT include extremely complicated demolitions work in public places, which would have involved a very large number of people and could hardly have been missed by the firefighters who explored a great deal of the building after the impact and prior to the collapse. |
| quote: | Foxx,
Perhaps your source is better. Fine, we'll go with that, but you've miscalculated, two different ways.
First, if you like FEMA's numbers, there were 10,000 gallons on the plane, and 3,000 were consumed in the initial fireball- leaving 7,000, not 3,500.
Second, at least half of that heat (from the fireball) would have remained in the building, and that's a conservative estimate- this is a confined space, and heat radiates (there isn't time for conduction, and convection doesn't occur in solid materials), so the bulk of the radiated heat would have been absorbed by the building directly rather than radiated out into the surrounding air; 75% might be a more realistic figure- but we'll go with 50%, to be conservative. So we'll add 1,500 gallons worth of energy to our budget. So that's 8,500 gallons worth, all told.
8,500 gallons is 32,176l. At 35MJ/l, that's 1,126,160,000,000J, 1.126TJ, which is still 312,822kWh. And remember, this was expended on, at most, three floors. So one floor would have gotten 104,274kWh, from the jet fuel alone. And that assumes that it was evenly distributed; most likely, one floor got more than the other two, but we'll take this conservative estimate.
Meanwhile, the contents of the floor would have added a further 346,000kWh, as previously calculated. This adds up to 450,274kWh per floor. In Joules, this is 1,620,986,666,667J, 1.62TJ. Remember also that the energy of the burnable materials per floor was quite conservative; we assumed that only 2/3 of the floor would be loaded at under half of its capacity of 100lbs/sqft, and that 2/3 of the loading would be unburnable metal. Anyone who has ever moved a file cabinet knows that more than 3/4 of the weight is the paper inside; but we've made very conservative estimates here.
The specific heat of iron is 452J/kgK at room temperature. An inspection of the NIST material data webbook shows that the curve is relatively free from significant anomalies below 1,000K, but shows a large spike between 1,000K and 1,200K. This spike is due to the latent heat of fusion, that is, the heat required to bring the iron to its liquid phase, once the liquid temperature is achieved; this is discussed in Hoffman's paper as well, although his discussion is for water, and for latent heat of vaporization rather than latent heat of fusion. You can look up latent heat in Wikipedia if you need more help understanding it. The latent heat of fusion of iron is around 200,000J/kg. Now, note that this is only true if the temperature of the iron is high enough to begin to liquify it; and the melting temperature of iron is 2,785F, or 1,530C, or 1,805K. So unless we reach that temperature, we don't need to add in the latent heat of fusion.
The mass of steel used in the construction of a single tower of the WTC was 90,000t; dividing by the number of floors, that's 818t/floor. I should point out that this is an extremely conservative number; the steel beams were MUCH thicker low down on the tower, growing progressively thinner on higher floors; this would be appropriate not only because the remaining weight above a floor would depend on how high that floor was, and therefore how many stories remained above it, but also because using less steel higher up would reduce the static loading on lower floors by decreasing the weight of higher floors on top of them, which would in turn reduce the amount of steel that must be used lower down, further decreasing the static load; there is a point of diminishing returns, and in addition, the thinnest and therefore weakest parts must still be strong enough to resist the strongest possible winds; in addition, the concrete was uniform; but even so, we can see that higher floors would be lighter than lower ones. So actually, far more than half the weight of steel of the WTC towers was below the 55th floor; but we'll go with this very high figure to show how ridiculous it is to suppose that there was not enough heat to cause failure of a single floor.
That 818t is 818,182kg; at 460J/kgK, that means that
818182kg * 460J/kgK = 376,363,636J/K
would be required to heat the mass by 1K. Dividing this figure into our 1.62TJ, we find that the temperature increase of the steel would be 4307K. WOW! That's well beyond the melting point; so we're going to have to add in the latent heat of fusion. What we do is figure out how much heat was necessary to raise the temperature to 1,805K from room temperature (300K), subtract that, and figure how much steel got liquified as a percentage based on how much latent heat could be supplied.
We start with a temperature rise of 1,505K (subtract that 300K from the melting point) and multiply by our 376,363,636J to raise the mass of steel 1K; then we take that figure and subtract it from our 1.62TJ. Whatever remains is contributed to latent heat, and we'll see how much steel we manage to liquify. Thus,
1505K * 376,363,636J/K = 566,427,272,180J = 566GJ
1,620,986,666,667J - 566,427,272,180J = 1,054,559,394,487J = 1.05TJ
Hmmm, we have most of our energy left- we only used a bit under a third of it bringing the steel to its melting temperature. OK, so how much of it could we have melted?
1,054,559,394,487J / 200,000J/kg = 5,272,796kg. But wait a minute- we only have 818,182kg! So this is enough energy to melt ALL of it, four or five times over!!! And plenty more to heat it up EVEN FURTHER!
Obviously, the fire never came close to consuming all the burnable material in a story; steel softens long before it melts, and loses a great deal of its strength before it gets anywhere close to melting; a plot of the Young modulus (the measure of elasticity of a material) of steel against temperature shows that most of steel's strength is gone before it gets to 700C, or 900K. When the steel's strength is gone, it collapses- and that means the floor it's on collapses- and then we have the much-maligned "pancake" model. It's certain that collapse occurred long before all the material on a single floor was burned. In addition, we can see that the heat from the jet fuel was not enough to raise the temperature high enough to soften the steel; it took the paper, wood, cloth, and plastic to do that, and it took a while for enough of it to burn to heat the steel far enough to weaken it enough to cause collapse. This dovetails with the fact that it took a while for the building to collapse.
Thus we see that there was more than sufficient energy, even without the jet fuel, to cause a floor to collapse; and once a floor collapsed, there was sufficient force to collapse the next, and that force could only increase as the mass accelerates and as the mass grows due to another floor and another and another being added to it. Meanwhile, the heat created by the burning contents (now greatly increased in rate due to the movement of air caused by the collapse (ever use a bellows on a wood fire?), and the addition of heat from the kinetic energy of the collapse) added to the heat of the friction of the collapse, accounts for the pyroclastic dust cloud and for the melted steel in the basement.
All of the calculations are quite conservative; more realistic estimates could increase the available energy by a factor of more than 2.
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