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I already demonstrated that is incorrect.
The stiffness is the same in every case. I only changed the mass.
psik
Your toy stiffness does not scale to an actual building a quarter mile high with an acre on each level. You have proven nothing but that you can construct irrelevant models.
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It was not intended to scale. It is the fact that the behavior changes with mass and its distribution which demonstrates that the mass and its distribution must be known about the WTC to analyze what happened on 9/11.
So why don’t we know the quantities of steel and concrete on every level of the towers after SEVEN YEARS? It is hilarious that most of the people in the nation that put men on the Moon 40 years ago don’t comprehend enough Newtonian physics to see the need for that information to analyze a grade school physics problem. 
Here are some TOYS for you:
The laws of physics are incapable of caring whether or not you call an object a toy. The physics does not change. Of course if someone does not have the brains to understand it then they must resort to name calling.
The mass of my tower has to respond to the impacts and the conservation of momentum will apply regardless of size. So why aren’t the GENIUSES who claim to know physics demanding to know the distributions of steel and concrete in the WTC? I haven’t noticed Richard Gage saying anything about that. I asked him in Chicago in May of 2008. He said the NIST wasn’t releasing accurate blueprints. But he is an architect and has engineers in his organization. They should be able to design the buildings with today’s computing power. It is not like they have to do it completely from scratch. Gravity hasn’t changed since the 1960s.
psik
Right, that is why the building in China did not fall because, besides not being struck by a plane, the engineers did check the actual materials and techniques used on the twin towers. When the Beijing tower was left still standing it demonstrated that the engineers found values and measurements that were valid and that they learned valuable lessons from what happened in 9/11.
Unfortunately you have only demonstrated that you are willing to learn only lessons from models.
Do you know the exact composition of the moon? If not, the landing can’t be confirmed.
In oscillatory motion, energy is transferred back and forth from kinetic (the velocity, in other words) to potential (the strain in the compliant member). As I pointed out previously, both stiffness and mass are necessary for determining oscillatory motion. However, the maximum displacement occurs when the velocity is zero.
The stiffness of the structure is determined more by the structure itself than the stiffness of the material. A thought experiment: A pile of 250 shims, each 0.001" thick, weight the same as a single 0.250" thick bar. The bending stiffness of the shim pile, however, is much less.
And the damping. And the energy transferred by the impact. To produce what appears to be approximately the same maximum displacement.
The physics doesn’t change, and that means behavior is different at different scales. This isn’t a change in the physics, it’s a change in the relative importance of different effects. This is why, for example, ants can carry many times their own weight but elephants can’t.
It’s pretty clear that you don’t really understand the physics behind the experiments you’re performing; moreover, you don’t really understand the differences between what happens at the smaller experimental scale and full-scale building. Hopefully you won’t get defensive about this, but take it as an opportunity to educate yourself.
New to this thread, eh? 
Since all you seem capable of doing is parroting your own silly question ad nauseam, without suggesting any solution of your own, I am putting aside my reluctance to aggravate the stuation by pointing out that you are trolling.
You may continue to post to this thread if you begin providing something of substance and as long as you do not ask this same stupid question, (which you refuse to research despite being shown where to find the answers), again.
[ /Moderating ]
Calling a model a toy, (particularly when it is not actually to be used in constructiion), is not name-calling.
However, direct personal insults are not permitted in this forum, hence your Warning for this behavior.
[ /Moderating ]
Or, to be more precise (and after further thought), the maximum displacement in any oscillatory mode occurs when the velocity is zero. For a tall structure loaded near the top, most of the energy would go into the first bending mode, which is indeed what psikeyhackr’s experiment shows. Since the first mode also gives the greatest deflection, concentrating on that mode when calculating maximum deflection isn’t unreasonable.
In any case, the following:
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psikeyhackr wants to know the distribution of mass in the building in order to calculate maximum deflection. However, mass distribution is of limited or no use in calculating maximum deflection; he should want stiffness.
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psikeyhackr wants to know maximum deflection in order to calculate energy transferred to the building and thus the percentage of the plane’s kinetic energy that did structural damage. However, the severity of the structural damage depends on exactly what members are damaged and what form the damage takes. Energy isn’t a substitute for severity.
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Presumably, psikeyhackr wants to know about structural damage to make some conclusion about how much the building was weakened by the plane impact. However, the answer is self-evident: not enough to collapse the building. Subsequent fires, however, weakened the building.
So psikeyhackr wants the wrong information to make an irrelevant calculation with a useless answer. Again, calculations and models can be useful, but it’s important to understand the limitations of the calculations and models, and how they relate to real life.
And he’s been waiting NEARLY EIGHT YEARS to do so.
I want to hear more about Psikey’s toy stiffie.
Or, then again, maybe not… :eek:
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But didn’t that information have to be determined before construction of the buildings was even begun? That was before the Moon landing. Didn’t getting to the Moon require knowledge of Newtonian physics?
July 20th will be the 40th anniversary of the Moon landing.
It is pretty pathetic that most Americans can’t understand enough about Newtonian physics to figure out that is ridiculous to believe that a 200 ton airliner could destroy a 400,000 ton building and not demand to know the distributions of steel and concrete in the building. And a $400 netbook is more powerful than any computer that existed in the 60s.
Has the country gone down hill since 1969 or were most Americans stupid then too?
psik
Yes, that is suspicious, or at least it would be if the destruction was based on Newtonian mechanics. It was actually applied thermodynamics. Y’know, heat and junk.
Now be fair, Bryan. psikeyhackr has pointed out a fatal flaw* in 9/11 conspiracy theories, and we should respect him for that.
- If it’s obviously physically impossible for an aircraft to destroy a huge building, then conspirators would sure have picked another cover story for 9/11, wouldn’t they?
To sum things up:
Too bad they are all false, pick your fav and I shall debunk it. I don’t debunk random web lists but engage in discourse and debate.
No. You do not want any such thing–or, at least, you do not want to express such an interest in Great Debates. (I do recognize the attempt at humor based on the oscillating model conversations, but it is still not appropriate.)
Knock it off.
[ /Modding ]
#2 was demonstrated to be false in this very thread.
The problem with this 9/11 business is the assumptions people start out with. It is in the title of this thread.
“Conspiracy Theory”
The question is whether or not a normal airliner weighing less than 200 tons can destroy a 1360 foot skyscraper weighing more than 400,000 tons in less than 2 hours and make it collapse in less than 18 seconds. Any and all conspiracy theories are irrelevant. Answer that question first and then move on to who and why and how.
But the skyscraper must be understood to address that question. How can that be done without even knowing the distribution of steel and concrete?
psik