The Physics Of WTC 7

[E.L.C.]

So I'll take a chance and put this here. It's not about conspiracy, how it could have been done, why it might have been done or who might have done it.... Please, just the physics. Critique this analysis, add to it, or just pick the one that you think is correct and why.... sort of an informal pole/discussion?

THE UNRESOLVED MYSTERY OF WTC 7

Images courtesy of KokomoJojo

Shyam Sunder, of the NIST, states free fall only happens when an object (or building) “...has no structural components below it.” He says despite the existence of structural components (mass) below it, WTC 7 went into free fall as if through air for eight stories, or 105 feet.

David Chandler, a retired physics teacher, states free fall only happens (to a building) when an "....external force removes the supporting structure." He says energy would have to to be added from some external source to remove structural components (mass) below it for free fall to occur as if through air for eight stories, or 105 feet.

Chart courtesy of KokomoJojo

They agree that WTC 7 fell at gravitational acceleration for 2.25 seconds, or 105 feet but....

There can be only one, they cannot both be true.... Or can they?

Is it Chandler on the left, or Sunder on the right?

My schematic animated representations of both theories.​

 

[ZenBubba]

Chandler's revised video makes sense to me.

I'm assuming you have seen it. I can't post it because I don't have enough posts.

It's title is: Physics - WTC7 Freefall by David Chandler - AE911Truth.org

 

[mamooth]

If all the support girders have already broken, then you do get close to free-fall speeds, at least until the fall reaches a still-reinforced section. That's exactly what happened with WTC7 during those 2.25 seconds.

Hence, Sunder is correct. There were no supporting elements below, because the support girders had broken.

Chandler, however, is out to lunch. "External force" is evasive babble, because girders are always under "external force". It doesn't require a controlled demolition to break a girder, there is zero evidence of any controlled demolition, and none of the controlled demolition theories make any sense at all.

 

[LA RAM FAN]

If all the support girders have already broken, then you do get close to free-fall speeds, at least until the fall reaches a still-reinforced section. That's exactly what happened with WTC7 during those 2.25 seconds.

Hence, Sunder is correct. There were no supporting elements below, because the support girders had broken.

Chandler, however, is out to lunch. "External force" is evasive babble, because girders are always under "external force". It doesn't require a controlled demolition to break a girder, there is zero evidence of any controlled demolition, and none of the controlled demolition theories make any sense at all.

Mammoth has been caught lying just like Sundar.Just like sunder,he lies in the fact there is OVERWHELMING evidence that there was a controlled demolition.

The Bush/Obama dupes here cant get around the facts that 9/11 is just like the jfk assassination in the fact that many witnesses that came forward giving versions of events different from the governments wound up dying in very mysterious deaths.

Barry Jennings testimony shreads to pieces the lies of the NIST report in the fact that he heard explosions going in the basement BEFORE the twin towers even fell.

Mammoth and others always blatantly ignore the fact as well that there were many other buildings in the area much close to the towers than bld 7 with far more extensive damage done to them and far more severe fires yet they did not collapse.

Barry Jennings was a convient death for NIST because his testimony would have shread to pieces the lies of NIST.His death was obviously a murder in the fact his death came just days before NIST gave its report to the public. there was this one lady who went on jones show as well talking about hearing explosions in the towers and telling jones not to believe the official story if she would up dying because she would never take her own life.after she went on jones show,she was found hanging from the ceiling and it iwas ruled a suicide.guess people like mammoth here think she changed her mind about killing herself.

then there is the lady of the truth movement in new york for the familys who went to Obama and asked him to reopen the investigation who wound up dying in a plane crash later on.

 

[E.L.C.]

Far out man! Thanks ZenBubba and mamooth. I want to go ahead but this thread has to be clean or I'm getting out of here. I reported the post by 9/11 inside job as having nothing to do with the topic. If this is really a science forum, that post will be removed. I'll post then.... Am I being unreasonable?

 

[flacaltenn]

Im assuming the real vid on the right is actual wtc7 collapse. Clearly elements of the roof are in near free fall thru the interior of the building well before the any part of steel exterior framing begins to move.

at that point, its amatter of time before enough heat strssed key support is taken out by the roof sections. That and unknown seismic and shock damage from the earlier building collapses.

Yes it does look like free fall. But im pretty sure that the objection of a demolition job is NOT to approach free fall rates for the top section of the structure..

 

[eots]

im assuming the real vid on the right is actual wtc7 collapse. clearly elements of the roof are in near free fall thru the interior of the building well before the any part of steel exterior framing begins to move.

At that point, its amatter of time before enough heat strssed key support is taken out by the roof sections. That and unknown seismic and shock damage from the earlier building collapses.

Yes it does look like free fall. But im pretty sure that the objection of a demolition job is not to approach free fall rates for the top section of the structure..

lol

 

[eots]

if all the support girders have already broken, then you do get close to free-fall speeds, at least until the fall reaches a still-reinforced section. That's exactly what happened with wtc7 during those 2.25 seconds.

Hence, sunder is correct. There were no supporting elements below, because the support girders had broken.

Chandler, however, is out to lunch. "external force" is evasive babble, because girders are always under "external force". It doesn't require a controlled demolition to break a girder, there is zero evidence of any controlled demolition, and none of the controlled demolition theories make any sense at all.

so how do you suggest all girders came to be all broken ? Small office fires ?

 

[mamooth]

7 World Trade Center - Wikipedia, the free encyclopedia
---
The fires burned out of control during the afternoon, causing floor beams near column 79 to expand and push a key girder off its seat, triggering the floors to fail around column 79 on Floors 8 to 14. With a loss of lateral support across nine floors, column 79 buckled – pulling the east penthouse and nearby columns down with it. With the buckling of these critical columns, the collapse then progressed east-to-west across the core, ultimately overloading the perimeter support, which buckled between Floors 7 and 17, causing the remaining portion of the building above to fall downward as a single unit.
---

There are 3 stages to the collapse.
-- 1.75 seconds of beam-buckling, where the rooftop only dropped around 10 feet
-- 2.25 seconds of near free-fall
-- 1.40 seconds of slower fall, as the debris hit still-supported sections.

The cascading failure due to the loss of one column is widely regarded as a design flaw.

 

[orogenicman]

What physics, where? Doesn't this belong in a conspiracy theory forum somewhere, and not the science forum?

 

[rightwinger]

F= M x a

All you need to know. Thanks Dr Newton

 

[flacaltenn]

im assuming the real vid on the right is actual wtc7 collapse. clearly elements of the roof are in near free fall thru the interior of the building well before the any part of steel exterior framing begins to move.

At that point, its amatter of time before enough heat strssed key support is taken out by the roof sections. That and unknown seismic and shock damage from the earlier building collapses.

Yes it does look like free fall. But im pretty sure that the objection of a demolition job is not to approach free fall rates for the top section of the structure..

lol

The roof structures are clearly falling rapidly before the frame starts to collapse. I wrote that b4 even reading a summary like mamooth provided. I suppose that COULD be funny, but its just a matter of scientific evidence in this forum. Youre talking to a guy who only CARES about the "physics" and the evidence. NOT the political implications.


Ive got my own conspiracies to hawk.

 

[LAfrique]

So I'll take a chance and put this here. It's not about conspiracy, how it could have been done, why it might have been done or who might have done it.... Please, just the physics. Critique this analysis, add to it, or just pick the one that you think is correct and why.... sort of an informal pole/discussion?

THE UNRESOLVED MYSTERY OF WTC 7

Images courtesy of KokomoJojo

Shyam Sunder, of the NIST, states free fall only happens when an object (or building) “...has no structural components below it.” He says despite the existence of structural components (mass) below it, WTC 7 went into free fall as if through air for eight stories, or 105 feet.

David Chandler, a retired physics teacher, states free fall only happens (to a building) when an "....external force removes the supporting structure." He says energy would have to to be added from some external source to remove structural components (mass) below it for free fall to occur as if through air for eight stories, or 105 feet.

Chart courtesy of KokomoJojo

They agree that WTC 7 fell at gravitational acceleration for 2.25 seconds, or 105 feet but....

There can be only one, they cannot both be true.... Or can they?

Is it Chandler on the left, or Sunder on the right?

My schematic animated representations of both theories.​

The destruction of the World Trade Towers were planned-loophole demolitions. Everything from the astronomical insurance on asbestos-infested World Trade Towers to evacuation of buildings on eve of 911/2001 and Arabs easily gaining access to cockpits of US planes are evidence that those buildings were intentionally, unlawfully and cold-bloodedly demolished.


Who Profited? 9-11 Research: Controlling Interests


Asbestos-Infested World Trade Towers - On the ruins of the World Trade Center


Unlawful Demolition Instead Of Abatement - 9-11 Research: Asbestos in the WTC

 

[eots]

im assuming the real vid on the right is actual wtc7 collapse. clearly elements of the roof are in near free fall thru the interior of the building well before the any part of steel exterior framing begins to move.

At that point, its amatter of time before enough heat strssed key support is taken out by the roof sections. That and unknown seismic and shock damage from the earlier building collapses.

Yes it does look like free fall. But im pretty sure that the objection of a demolition job is not to approach free fall rates for the top section of the structure..

lol

its amatter of time before enough heat strssed key support is taken out by the roof sections
The roof structures are clearly falling rapidly before the frame starts to collapse. I wrote that b4 even reading a summary like mamooth provided. I suppose that COULD be funny, but its just a matter of scientific evidence in this forum. Youre talking to a guy who only CARES about the "physics" and the evidence. NOT the political implications.


Ive got my own conspiracies to hawk.

'its amatter of time before enough heat strssed key support is taken out by the roof sections'

...IS NOT SCIENCE

 

[Coyote]

Moved to proper forum.

 

[whitehall]

Free fall from that height would take 9.22 seconds. It took the Tower about 21 seconds to hit the ground. Therefore in the strict science of physics the Tower could not have been in free fall.

 

[KokomoJojo]

Chandler's revised video makes sense to me.

I'm assuming you have seen it. I can't post it because I don't have enough posts.

It's title is: Physics - WTC7 Freefall by David Chandler - AE911Truth.org

here:

[ame=http://www.youtube.com/watch?v=CpAp8eCEqNA]Physics - WTC7 Freefall by David Chandler - AE911Truth.org - YouTube[/ame]

posted it for you

 

[E.L.C.]

Of course, it's just my opinion but....

Fraud Site!​

 

[KokomoJojo]

So I'll take a chance and put this here. It's not about conspiracy, how it could have been done, why it might have been done or who might have done it.... Please, just the physics. Critique this analysis, add to it, or just pick the one that you think is correct and why.... sort of an informal pole/discussion?

THE UNRESOLVED MYSTERY OF WTC 7

Images courtesy of KokomoJojo

Shyam Sunder, of the NIST, states free fall only happens when an object (or building) “...has no structural components below it.” He says despite the existence of structural components (mass) below it, WTC 7 went into free fall as if through air for eight stories, or 105 feet.

David Chandler, a retired physics teacher, states free fall only happens (to a building) when an "....external force removes the supporting structure." He says energy would have to to be added from some external source to remove structural components (mass) below it for free fall to occur as if through air for eight stories, or 105 feet.

Chart courtesy of KokomoJojo

They agree that WTC 7 fell at gravitational acceleration for 2.25 seconds, or 105 feet but....

There can be only one, they cannot both be true.... Or can they?

Is it Chandler on the left, or Sunder on the right?

My schematic animated representations of both theories.​

Not sure what you expect in terms of a response. your limitations in the OP almost restrict this to math based on facts that unfortunately we are not privy to and requires that we make certain presumptions. What are we supposed to presume for a starting point or is freefall the central issue and point to expand from? Additional clarification?

Nist only timed it for 18 floors. I timed the whole thing conservatively at 7 seconds and change. It freefell for well over 75% of its height. I did not use software like chandler however. (too much work, stop watch works fine for my purposes LOL)

otherwise an obvious target would be to investigate how, 2/3rds of the way to the right of the face you will see the light showing through. Same place you can see all the windows breaking on the real structure.

It begs the question how that narrow part of the building gave way to the extent that we see the light passing through it. Nist has not offered any explanation for it but the only way we can see light is if what was there blocking it is not longer there. So how did the failure of column 79 or whatever one they claim transfer to precisely 2/3rds of the way across the building and wipe that section out?

How strange thought I would get the original model and now I have differing nist models?

[ame]http://www.youtube.com/watch?v=FuyZJl9YleY#t=26[/ame]

how odd in the video above he has 2 different nist models??????




so here are some physics and observations from chandler;

The clearest discrepancy is the deformation of the external structure in the model, which does not occur in the observed collapse. Mr. Chandler identifies a second glaring discrepancy, saying:

“One fact we do know about NIST’s model [software] is it does not allow for free fall. The best they could do is 5.4 seconds for the building to crumple down through 18 floors. Crumpling absorbs energy, and that makes free fall impossible. There’s nothing in the models we have been shown that even resemble a three-stage collapse with a free fall component. After all, as Shyam Sunder put it himself, ‘free fall happens only when there are no structural components below the falling section of the building.’ Any natural scenario is going to involve a progression of failures and these don’t happen instantaneously.”
​

Although NIST’s model is false, based on its failure to reproduce the observed collapse, it cannot be falsified because NIST did not release its modeling data. Mr. Chandler explains:

“NIST claims their computer model can account for the observed phenomena, so let’s look at NIST’s model – except we can’t. The software they used to do the modeling is available, but their model actually consists of all the numbers and measurements and assumptions together with any tweaks to the system they might have used to get it to come out the way they wanted. If that information were released, their results could be checked by anyone with the appropriate skills and software tools. But NIST has not released the numbers. All we have been shown are some of the selected animated outputs they were able to get their model to produce… The very fact that NIST has not released their model strongly suggests they don’t want their results checked. In other words, their results are intended to be taken strictly on faith.”
​

References


[ii] NIST NCSTAR 1-9A, “Global Structural Analysis of the Response of World Trade Center Building 7 to Fires and Debris Impact Damage,” Washington, DC. November 2008. p.111. http://wtc.nist.gov/NCSTAR1/NCSTAR1-9index.htm

 

[E.L.C.]

Nothing you did KokomoJojo.... I just wanted a clean thread. I asked the Moderator in "Science" to help me with that, but instead of helping me, he/she/it just went ahead and dumped a straightforward science question into the "Consptracy Theory" section.

Plus.... There's something positively creepy about the way posters like daws101 (among others) carry on. I wouldn't say they're government sock puppets.... but it definitely wouldn't surprise me if it turned out they were either. I'm done.... there are other things to see.

Take care man....

See you down the old trail !