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ergo123
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USA
810 Posts

Posted - 10/02/2006 :  15:27:51   [Permalink]  Show Profile Send ergo123 a Private Message
Hi "Trogdor":

I don't recall ever citing or reading the article you linked above. The photo sure shows a big cloud of dust, though.

But now having read the article, which of the inputs to Hoffman's calculations is incorrect? What are the correct inputs? and what is the net result in the calculations based on the new inputs? It's fine to point out someone might be in error. But MIGHT is easy to throw around. Be as thorough as you claim to be and provide us with the correct formula if Hoffman's is wrong.

And according to Wikipedia, Little Boy was a 15 kiloton (equivalent) bomb. If we convert that to KWHs we get 15,538,200 KWH (15,000 metric tones = 33,060,000 pounds; 33,060,000 lbs. @ .47 KWH/lb (the force in a pound of dynamite) = 15,538,200 KWH). Hoffman's estimate of the energy to cause and disperse the dust is 14,447,000 KWH, or just less than 1 "Hiroshima." At least one of us got the math wrong. If it is me, please point out my error.

As for "scientist talk..." when someone complains that weight was not factored in when the mass clearly was, sometimes a little quip like that comes out. Besides, Dave is 40 years old. I'm sure he can take a little banter. And remember--no matter how old someone is, they are still just a person. No matter how harsh you might find the words they use, they are just words being used by a person. Try not to be intimidated by words or people. That goes for you, too, Dave!

No witty quotes. I think for myself.
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Dude
SFN Die Hard

USA
6891 Posts

Posted - 10/02/2006 :  15:55:28   [Permalink]  Show Profile Send Dude a Private Message
ergo123 said:
quote:
point of the article was to show that the mass (that's "scientist talk" for weight)


Really, you have some brass plated balls. You have the audacity to question others on their knowledge of physics, and then you make a statement that equates mass and weight?

FYI, they are not the same thing.


Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong.
-- Thomas Jefferson

"god :: the last refuge of a man with no answers and no argument." - G. Carlin

Hope, n.
The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth
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ergo123
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USA
810 Posts

Posted - 10/02/2006 :  15:57:22   [Permalink]  Show Profile Send ergo123 a Private Message
Dude: Like I said before. I'm going to hold off on that issue (how it was done) until I'm convinced that it couldn't be due to gravity alone. So far, no one has provided any convincing evidence for the conspiricy theory that includes a gravity-only component to explain the collapse of WTC 1,2 & 7. But it's only been about 24 hours.

No witty quotes. I think for myself.
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Dude
SFN Die Hard

USA
6891 Posts

Posted - 10/02/2006 :  16:09:42   [Permalink]  Show Profile Send Dude a Private Message
ergo123 said:
quote:
So far, no one has provided any convincing evidence for the conspiricy theory that includes a gravity-only component


Your continued use of imbecilic and inapropriate terminology will earn you nothing but ridicule.

Your obvious implication, by denying the obvious reasons for the building collapse(intense fire, weakened steel, gravity), is that some other human agency besides crashed airliners is responsible.


Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong.
-- Thomas Jefferson

"god :: the last refuge of a man with no answers and no argument." - G. Carlin

Hope, n.
The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth
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Paulos23
Skeptic Friend

USA
446 Posts

Posted - 10/02/2006 :  16:10:11   [Permalink]  Show Profile  Visit Paulos23's Homepage Send Paulos23 a Private Message
A FAQ was put out by the NIST on the WTC collapse due to the number of questions they where receiving. Check out questions 2, 4, 5,11, and 12 about their thoughts on it being demolitions.

http://wtc.nist.gov/pubs/factsheets/faqs_8_2006.htm

Also, the dust may not have been as much concrete in the dust as you think: http://www.janegalt.net/blog/archives/004194.html


You can go wrong by being too skeptical as readily as by being too trusting. -- Robert A. Heinlein

Facts do not cease to exist because they are ignored. -- Aldous Huxley
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ergo123
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USA
810 Posts

Posted - 10/02/2006 :  16:26:41   [Permalink]  Show Profile Send ergo123 a Private Message
Dude: Of course that's the implication. But what's the point of exploring the whys and hows behind the implication before one knows if the argument that leads to the implication is true?

And to what "imbecilic and inapropriate terminology" do you refer? Is it that I refer to the government story of what happened a conspiracy theory? Well isn't the official theory that 19 or more men conspired to attack several US buildings with planes? And that after 2 of the buildings were hit gravity was the force that brought them down? What do you call that?

No witty quotes. I think for myself.
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R.Wreck
SFN Regular

USA
1191 Posts

Posted - 10/02/2006 :  17:16:01   [Permalink]  Show Profile Send R.Wreck a Private Message
quote:


ergo123 said:

But some of the other sites (like scholars for truth.org) show evidence that it is physically impossible for the buildings to have fallen as fast as they did due to gravity alone.

and

As for my comment about it being impossible for the buildings to have fallen so quickly, I meant that if it was a gravity-only collapse. The sources I've seen conclude that the only way they could have fallen as fast as they did was via controlled demolition

and

So, Yes, R.Wreck--controlled demolition explosives aid the collapse process by getting those pesky and very strong floor supports out of the way.


Maybe I'm just not understanding your application of some terms here.

Whether it is a controlled demolition or due to the after affects of an airliner crashing into the building, the building will fall at a maximum speed dictated by gravity. Once the structure is sufficiently weakened, any building collapse is due to "gravity only", and it will not fall any faster unless some other external force is applied.

Are you claiming that some extra force was applied to make the building fall faster than it's speed due to gravity alone? Or are you claiming that a controlled demolition will always result in a faster collapse than one due to "uncontrolled" factors?


The foundation of morality is to . . . give up pretending to believe that for which there is no evidence, and repeating unintelligible propositions about things beyond the possibliities of knowledge.
T. H. Huxley

The Cattle Prod of Enlightened Compassion
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Dude
SFN Die Hard

USA
6891 Posts

Posted - 10/02/2006 :  17:39:22   [Permalink]  Show Profile Send Dude a Private Message
ergo123 asked:
quote:
And to what "imbecilic and inapropriate terminology" do you refer?


Go read the first paragraph of your first post in this thread. That, and all other references by you that refer to the collapse of the buildings as "the government's conspiracy theory", are imbecilic use of terminology.


Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong.
-- Thomas Jefferson

"god :: the last refuge of a man with no answers and no argument." - G. Carlin

Hope, n.
The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth
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trogdor
Skeptic Friend

198 Posts

Posted - 10/02/2006 :  17:54:17   [Permalink]  Show Profile Send trogdor a Private Message
quote:
Originally posted by ergo123

Hi "Trogdor":

I don't recall ever citing or reading the article you linked above. The photo sure shows a big cloud of dust, though.

I had heard you talk about the expansion of the dust cloud “over the whole city.” You gave no source so I tried to find what you were talking about myself. I found this. If this was not what you were talking about, then I messed up, but it just reinforces my point about citing sources.

quote:
But now having read the article, which of the inputs to Hoffman's calculations is incorrect? What are the correct inputs? and what is the net result in the calculations based on the new inputs? It's fine to point out someone might be in error. But MIGHT is easy to throw around. Be as thorough as you claim to be and provide us with the correct formula if Hoffman's is wrong.

And according to Wikipedia, Little Boy was a 15 kiloton (equivalent) bomb. If we convert that to KWHs we get 15,538,200 KWH (15,000 metric tones = 33,060,000 pounds; 33,060,000 lbs. @ .47 KWH/lb (the force in a pound of dynamite) = 15,538,200 KWH). Hoffman's estimate of the energy to cause and disperse the dust is 14,447,000 KWH, or just less than 1 "Hiroshima." At least one of us got the math wrong. If it is me, please point out my error.

no, I made a mistake, and now I've gone and shot my mouth off.
But my point still stands. If Hoffman's calculations would indicate that it would be necessary for there to be nearly 15000 tons of TNT in each tower without anyone knowing, wouldn't that indicate that there may be a problem with his math?


all eyes were on Ford Prefect. some of them were on stalks.
-Douglas Adams
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filthy
SFN Die Hard

USA
14408 Posts

Posted - 10/02/2006 :  18:00:39   [Permalink]  Show Profile Send filthy a Private Message
Perhaps I can clear up what might be a misconception, here.

It is thought, and I've heard this before, that the explosive implosion somehow sucks the building down. This is not the case. Rather, the main support members are shape-charged in such a way that the walls pull in and the rest of the structure falls by gravity.

Think of felling a large tree. First, you make a notched undercut facing the direction you wish to lay the tree. Then you make the backcut -- the felling cut -- and gravity does the rest. If you have done it properly, you could drive a stake with that tree.

That, very basicly, is how these demolitions are done. It's all highly technical, involving engineers and grunt laborers as well as the powder monkey gang. Also, no two buildings are the same, thus no two sets of charges are similar beyond using composition explosives.

If I were investigating something like this, the first thing I'd look for would be the persons who had most recently checked out the building's blueprints. Same thing, opposite side if I were planning to do the deed myself, using chemical explosives.




"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)

"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres


"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude

Brother Boot Knife of Warm Humanitarianism,

and Crypto-Communist!

Edited by - filthy on 10/02/2006 18:05:07
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H. Humbert
SFN Die Hard

USA
4574 Posts

Posted - 10/02/2006 :  18:12:42   [Permalink]  Show Profile Send H. Humbert a Private Message
This page is the best refutation of the "Loose Change" conspiracy video I've seen yet.


"A man is his own easiest dupe, for what he wishes to be true he generally believes to be true." --Demosthenes

"The first principle is that you must not fool yourself - and you are the easiest person to fool." --Richard P. Feynman

"Face facts with dignity." --found inside a fortune cookie
Edited by - H. Humbert on 10/02/2006 18:13:22
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ergo123
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USA
810 Posts

Posted - 10/02/2006 :  18:50:15   [Permalink]  Show Profile Send ergo123 a Private Message
R.Wreck: Neither. I'm stating that some scientists claim that the only way a building can come down at near free-fall speed is if the support structures holding up each floor are destroyed before the mass above a given floor reaches that floor. The bulk of the comments on this thread, however, have nothing to do with the speed of the collapse. Rather, they are concerned with another scientist who claims that the mass of the block of floors above the crash zone would not have enough energy to collapse the first impacted floor below the crash zone. That is, the strength inherent in the first impacted floor and the physical realities of propagation of force would have stopped the upper block of floors from collapsing the rest of the building. But of course, the buildings did collapse. So either that guy's calculations are wrong or, if his calculations are correct, each floor was floating in mid air. So far no one has shown his calculations to be wrong.

Trogdor: Oh come on, man. One need not have 15,000 tons of TNT to produce the energy needed. After all, Little Man was not 15,000 metric tones in weight. It weighed in (if memory serves) at just under 1,000 lbs. I'm sure there are explosives out there that pack more punch per pound than TNT. But let's first determine if the government's conspiricy theory is plausible in terms of whether the buildings would collapse if the blocks of upper floors hit the rest of the buildings. If that is proven plausible, the next step it to prove that the buildings, so collapsed, could occur as fast as they did if unassisted.

No witty quotes. I think for myself.
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Dave W.
Info Junkie

USA
26020 Posts

Posted - 10/02/2006 :  19:59:37   [Permalink]  Show Profile  Visit Dave W.'s Homepage Send Dave W. a Private Message
quote:
Originally posted by ergo123

To impact only the floor joist attachments...
Well, there is your problem, right there. To make the joist attactment points fail, all one has to do is overload the joists. There is no need to "impact only the floor joist attachments." Your strawman argument is therefore rejected.
quote:
And why do you think the commission was not allowed to examine WHY the buildings fell?
Show me evidence that the Commission "was not allowed to examine WHY the buildings fell," and perhaps I'll think of something. As things stand right now, it appears that the 9/11 Commission wasn't asked to examine that question. NIST sure was, though.
quote:
Ross points out that the supports WOULD have to buckle--but he does not include that in his energy audit. His energy audit shows the first impacted floor would not collapse EVEN WHEN IGNORING THE FACT THAT THE SUPPORTS WOULD HAVE TO BUCKLE AND THAT THAT WOULD ABSORB EVEN MORE ENERGY FURTHER PREVENTING A COLLAPSE.
Shouting isn't going to help, because you're definitely reading a different report than the one you linked to on page one of this thread, then, since the one I read said this:
Energy required;
    Momentum losses 1389MJ
    Plastic strain energy in lower impacted storey 244MJ
    Plastic strain energy in upper impacted storey 215MJ
    Elastic strain energy in lower storeys 64MJ
    Elastic strain energy in upper storeys 126MJ
    Pulverisation of concrete on impacting floor 304MJ
    Pulverisation of concrete on impacted floor 304MJ
    Total Energy required 2646MJ
Now, the elastic and plastic strains are all the energies required to buckle a steel column. If we disregard them, as you claim that Ross claims we can, and we disregard the pulverization (ditto), then all we're left with is a 1389 MJ energy drop due to the collision itself of 16 floors onto a 17th, leaving us with an energy surplus of 867 MJ, so the collapse continues.
quote:
And Ross does not ignore how the building was built. He ignores things like floating floors and shrinking blocks which just can't occur.
Nobody is claiming that anything is floating except the people that Ross was responding to. Ross debunked a fictional collapse in which the building not only had floating floors but probably friction-free surfaces and point masses, too. Whoop-te-do. Ross' analysis doesn't touch on the important factors in the "official" version of events, in which a multiple floor buckling of one perimeter wall in each tower is what begins the collapse.
quote:
As for "Or a building in which the floors are hung from the supporting columns, rather than being pushed up by them," if the joist attachments were ATTACHED to the support columns, they were being pushed up by them.
You're missing the point, which is that to shear off the joist attachments, one only need to overload them. That's why the collapse continued.
quote:
Do you have any background in physics?
Why, do you?

- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too.
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Dave W.
Info Junkie

USA
26020 Posts

Posted - 10/02/2006 :  20:14:28   [Permalink]  Show Profile  Visit Dave W.'s Homepage Send Dave W. a Private Message
quote:
Originally posted by ergo123

The bulk of the comments on this thread, however, have nothing to do with the speed of the collapse.
Right, you failed to acknowledge the fact that free-fall from 93 floors up takes 8.3 seconds, while the collapse of 1 WTC took about 43% longer than that (even more if the NIST report is correct and parts of the core stood for an additional 15 to 25 seconds after the onset of collapse). Since you won't acknowledge even this simple point, there's nothing left to discuss about the speed of the collapse.
quote:
Rather, they are concerned with another scientist who claims that the mass of the block of floors above the crash zone would not have enough energy to collapse the first impacted floor below the crash zone. That is, the strength inherent in the first impacted floor and the physical realities of propagation of force would have stopped the upper block of floors from collapsing the rest of the building. But of course, the buildings did collapse. So either that guy's calculations are wrong or, if his calculations are correct, each floor was floating in mid air. So far no one has shown his calculations to be wrong.
His model is what's wrong, since it would not require buckling columns in order to continue the collapse of the floors of the actual buildings themselves. His calculations for his fictional building are probably correct, but the WTC towers weren't built like he claims. Your assertion that how the buildings were built is irrelevant is wholly incorrect, since otherwise you'd be forced to claim that Ross' model is correct even for a 110-story solid concrete block, or for a 110-story house of cards, both of which are absurd. Of course the architecture is relevant (and in this discussion, of paramount importance).
quote:
...whether the buildings would collapse if the blocks of upper floors hit the rest of the buildings. If that is proven plausible...
The only evidence you've presented that it is not plausible is Ross' incorrect analysis. When are we going to hear from you a criticial examination of NIST's claims, showing where their math is incorrect? If that's what you expect of us, will you not hold yourself to the same standard?

- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too.
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marfknox
SFN Die Hard

USA
3739 Posts

Posted - 10/02/2006 :  20:52:01   [Permalink]  Show Profile  Visit marfknox's Homepage  Send marfknox an AOL message Send marfknox a Private Message
ergo123 wrote:
quote:
Do you have any background in physics?
Are you implying that only someone with a background in physics can understand all the points of this discussion? If so, why are you even bothering to talk to anyone without a background in physics? Facts are facts. Math is math. As long as everyone is smart enough to comprehend the other's posts, credentials are irrelevant.

I might add that I don't see any large groups of physicists banding together to publicize the "government's 9-11 conspiracy".

"Too much certainty and clarity could lead to cruel intolerance" -Karen Armstrong

Check out my art store: http://www.marfknox.etsy.com

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