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9/11: Faster Than Free-Fall???

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posted on Oct, 18 2006 @ 02:18 PM
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One of the claims that the Scholars for 9/11 Truth use to prove their demolition theory of why the twin towers collapsed, is that the destruction of the towers happens faster than free fall which they say could only happen through the use of explosives.

Overview of New 9/11 Research


8. The destruction of the South Tower in 10 seconds and of the North in 9 is even faster than free fall with only air resistance, which would have taken at least 12 seconds, which, as Judy Wood has emphasized, is an astounding result that would have been impossible without extremely powerful explosives.


Which brings me to my question: How is it possible to fall faster than free fall?

Even if you removed the entire middle section of the building and simply dropped the roof section it is physically not possible to fall faster than free fall unless there was an object (like rockets, jet engine, etc) exerting an additional downward force on it.

So, at best (depending on your perspective) the building could only fall as fast as free fall... not faster than free fall. And that's only if the structure itself was cleared out of the way simultaneously eliminating resistance from the structure and also if air resistance was negligible. It seems to me that demolition explosives would direct force either in all directions or outward but not just downward making it fall faster than free fall.

Also, on a related point, how is the exact and ending point at which the structure has fully collapsed determined with the amount of debris floating around? Is there a clear view of when the collapse has been completed?

Maybe this is just a minor point but I think since the use of explosions seems to be the major alternative theory these days that this should be clarified.



posted on Oct, 18 2006 @ 02:54 PM
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Freefall is the velocity achievable by an object (in a vacuum) that starts at zero velocity and whose subsequent velocity is entirely derived from the conversion of potential energy (gravity). Objects can achieve faster than freefall if kinetic energy is applied to them. For example, imagine you have two ball bearings sitting on slightly inclined platforms in identical vertical vacuum tubes. For one you remove its stop and let it fall. For the other you have a pinball machine like plunger to launch it. Which ball will fall the faster?



posted on Oct, 18 2006 @ 02:58 PM
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Mecheng, those are very valid points. Be prepared for the onslaught as the CD theorist rush to defend their position.

Of course it is impossible to free fall faster than free fall. You don’t have to be a scholar to know that.

In another thread, the CDers posted pictures that clearly show that portions of the tower core took considerably longer to collapse then exterior walls which were in free fall, because they fell outside the building. Yet these same people still cling to the free fall myth.

The same thing with the WTC 7 collapse. No doubt that someone will post the highly edited and abbreviated collapse video that only shows the final portion of the building collapse. They like to point to this and say that the building offered no resistance to collapse, yet they ignore the fact that the part of the video that does show resistance to collapse was edited out.



posted on Oct, 18 2006 @ 03:00 PM
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Originally posted by jtma508
Freefall is the velocity achievable by an object (in a vacuum) that starts at zero velocity and whose subsequent velocity is entirely derived from the conversion of potential energy (gravity). Objects can achieve faster than freefall if kinetic energy is applied to them. For example, imagine you have two ball bearings sitting on slightly inclined platforms in identical vertical vacuum tubes. For one you remove its stop and let it fall. For the other you have a pinball machine like plunger to launch it. Which ball will fall the faster?



Where is that video of a giant foot stomping on WTC 7 when you need it?

So, was there a giant plunger opperated by Aliens in a UFO pushing down on the building?

Where there rocket motors mounted on the roof pushing downward?

Was there a giant electro-magnet hidden in the bedrock during the construction?



posted on Oct, 18 2006 @ 03:08 PM
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Originally posted by jtma508
For the other you have a pinball machine like plunger to launch it. Which ball will fall the faster?

Exactly. So what was the plunger? It couldn't have been explosives.
Even if all the explosives went of simultaneously and blew away the entire structure leaving only the roof behind, the roof could not fall faster than free fall.



posted on Oct, 18 2006 @ 03:24 PM
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A lot of these claims rest on things that "someone said" but for which there is no objective evidence (or there's doctored evidence.) I heard one today, about a "cordite smell" at the Pentagon and immediately wondered "who said there was one" and "just where was this person" and "do we have proof of that person's presence" and "can they demonstrate they know what cordite smell is and can distinguish it from other smells."

As someone has said of these, the whole "conspiracy" relies on the emergency workers and rescue workers and police officers who were there ALL tacitly agreeing to the death and injury of so many members of their profession and callously covering up evidence of this. If you know any firefighters (I know several) or cops (I know several), you'll know just how unlikely a scenario this is.



posted on Oct, 18 2006 @ 04:16 PM
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Ok, I emailed James Fetzer at Scholars for 9/11 Truth. And he basically said that the "collapse" duration, 10 seconds for the South tower and 9 seconds for North tower come from the NIST report. Scholars for 9/11 Truth claim these are faster than free fall. I calculated that they were near free fall. It's hard to determine for sure since you can't see everything because of the debris cloud. They really are talking about the "destruction" as opposed to the "collapse".

There's some good analysis of the collapse duration here... Speed of Fall which determines a "collapse" duration of up to 15 seconds. In any case the "proof" of demolition explosives comes from the assumption that the resistance of the building itself would create much longer collapse durations than that.

I also found this...
NIST Statement on Progressive/Disportionate Collapse Provisions which states...

In the course of its Investigation into the collapse of the World Trade Center Towers, NIST has not found any evidence that well-tied buildings performed unfavorably (or collapse earlier) than buildings that are not well-tied. In fact NIST has found that, had the major structural subsystems of the WTC towers not been tied together, the core of the towers would have collapsed earlier. The hat-truss tied the core to the perimeter walls of the towers, and thus allowed the building to withstand the effects of the aircraft impact and subsequent fires for a much longer time enabling large numbers of building occupants to evacuate safely.

...which IMO would seem to say that the building should have taken longer to come down than it did... that it was structurely sound.


[edit on 18-10-2006 by mecheng]



posted on Oct, 18 2006 @ 04:19 PM
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Originally posted by Byrd
A lot of these claims rest on things that "someone said" but for which there is no objective evidence (or there's doctored evidence.) I heard one today, about a "cordite smell" at the Pentagon and immediately wondered "who said there was one" and "just where was this person" and "do we have proof of that person's presence" and "can they demonstrate they know what cordite smell is and can distinguish it from other smells."

As someone has said of these, the whole "conspiracy" relies on the emergency workers and rescue workers and police officers who were there ALL tacitly agreeing to the death and injury of so many members of their profession and callously covering up evidence of this. If you know any firefighters (I know several) or cops (I know several), you'll know just how unlikely a scenario this is.


I might be that im at work at 2am, or that i simply am not as smart as you byrd.. but im lost as to what your implying in the last paragraph?

I hope I understand it right, but i agree if you mean the firefighters and cops stating something anything but the truth is unlikely, given the nature of there profession...

surely the cleanup workers would of found some sort of trace evidence of explosives or something as such at the WTC?

the pentagon is questionable, because its not like any common citizen would of been close enough to inspect and smell, immediately after.. its a guarded military complex, and thus to me means only military officials would be within distance to comment on the nature of the ' hole '



posted on Oct, 18 2006 @ 04:23 PM
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From the NIST FAQ page”
wtc.nist.gov...

NIST estimated the elapsed times for the first exterior panels to strike the ground after the collapse initiated in each of the towers to be approximately 11 seconds for WTC 1 and approximately 9 seconds for WTC 2. These elapsed times were based on: (1) precise timing of the initiation of collapse from video evidence, and (2) ground motion (seismic) signals recorded at Palisades, N.Y., that also were precisely time-calibrated for wave transmission times from lower Manhattan (see NCSTAR 1-5A).
As documented in Section 6.14.4 of NIST NCSTAR 1, these collapse times show that:
“… the structure below the level of collapse initiation offered minimal resistance to the falling building mass at and above the impact zone. The potential energy released by the downward movement of the large building mass far exceeded the capacity of the intact structure below to absorb that energy through energy of deformation.
Since the stories below the level of collapse initiation provided little resistance to the tremendous energy released by the falling building mass, the building section above came down essentially in free fall, as seen in videos. As the stories below sequentially failed, the falling mass increased, further increasing the demand on the floors below, which were unable to arrest the moving mass.”
In other words, the momentum (which equals mass times velocity) of the 12 to 28 stories (WTC 1 and WTC 2, respectively) falling on the supporting structure below (which was designed to support only the static weight of the floors above and not any dynamic effects due to the downward momentum) so greatly exceeded the strength capacity of the structure below that it (the structure below) was unable to stop or even to slow the falling mass. The downward momentum felt by each successive lower floor was even larger due to the increasing mass.
From video evidence, significant portions of the cores of both buildings (roughly 60 stories of WTC 1 and 40 stories of WTC 2) are known to have stood 15 to 25 seconds after collapse initiation before they, too, began to collapse. Neither the duration of the seismic records nor video evidence (due to obstruction of view caused by debris clouds) are reliable indicators of the total time it took for each building to collapse completely.



posted on Oct, 18 2006 @ 05:03 PM
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I think the 'faster than free fall' is not really true, an exaggeration taken too literally by some, on both sides of the argument. But doesn't matter...

Even if they had fell in say 20 secs it would still be too fast. Just look at the physics involved...

This is the conclusion, see the site for explanation...


In order for the tower to have collapsed "gravitationally", as we've been told over and over again, in the observed duration, one or more of the following zany-sounding conditions must have been met:

* The undamaged floors below the impact zone offered zero resistance to the collapse
* The glass and concrete spontaneously disintegrated without any expenditure of energy
* On 9/11, gravity was much stronger than gravity
* On 9/11, energy was not conserved

Source

The lower undamaged floors offered no resistance to the collapsing upper floors.

110 stories, even if the undamaged floors offered only 1 second of resistance the towers should have taken 110 seconds to completely collapse.
The only way the towers could have fell at the speed they did was if the lower floors offered no resistance. How could that be possible without the help of another energy source other than planes and fires?



posted on Oct, 18 2006 @ 05:05 PM
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Howwierd we don't need NIST to tell us how fast they fell. We have numerous videos of the collapses, enough to make up our own minds, thanx...



posted on Oct, 18 2006 @ 10:49 PM
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The ST9/11 group is calling for another investigation primarily, so by using the official collapse times, if those collapse times are wrong, then the government is responsible for throwing them out there to begin with. It's not the only thing they've said that's been wrong, by far, in my opinion.


Originally posted by mecheng
Which brings me to my question: How is it possible to fall faster than free fall?


Faster than free-fall with air resistance taken into account (on the surface of the Earth), in this case.

In a vacuum, something could fall faster than free-fall speed with terminal velocity from air resistance taken into account. So in this sense, faster than free-fall is possible, but requires a vacuum be created within the building.

The Towers did not fall at free fall speed, but more troubling than how fast they fell, is the fact that they fell at a constant velocity the whole time and never slowed down despite losing so much mass and encountering so much resistance.

WTC7 fell at free-fall speed (whether with or without air resistance taken into account I'm not sure), which suggests that it was demolished conventionally with air resistance taken out of the picture.


Also, on a related point, how is the exact and ending point at which the structure has fully collapsed determined with the amount of debris floating around? Is there a clear view of when the collapse has been completed?


Never seen one, but have looked.

[edit on 18-10-2006 by bsbray11]



posted on Oct, 18 2006 @ 11:01 PM
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As bsbray stated, the towers did not fall at - (inserting past his words - or faster) - than free fall. And it's a testament to how short the NIST report falls that they report something that numerous videos show to be wrong. While almost the entirety of the "lunatic conspiracy theory" world have rejected this erroneous accusation, the NIST is sitting as an engraved failure of our investment with its referral to the misinterpreted seismic record as an undeniable statement the towers fell faster than gravity.

Even the "official story supporters" have to admit this is a pretty pathetic failing by the paid organization.

EDIT: Actually I should refer to the "911 Commission Report" because they are the only extant document to refer to the erroneous "10 second" collapse time based on the seismic record. But this statement is based on now retracted NIST statements.

[edit on 10-18-2006 by Valhall]



posted on Oct, 18 2006 @ 11:05 PM
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I have to say though. If the building collapsed on itself wouldnt the vellocity not be constant? Cause wouldnt the building hit floors that were still pretty well intact that would slow it down? A constant speed makes it seem like it didnt collapse on itself



posted on Oct, 18 2006 @ 11:12 PM
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Originally posted by Pepperslappy
I have to say though. If the building collapsed on itself wouldnt the vellocity not be constant?


EXACTLY.

It should have slowed down or sped up or something. People who think the mass simply built up more and more should have be wondering why there wasn't positive acceleration. People who know better and realize that 80+% of the masses were ejected out of the footprints should be wondering why they did not slow down as the resistance increased.

Either way, work is being done. The initial falling mass only had so much potential energy, and it was working upon a body that was provided (or SHOULD have been providing) constant resistance for every column, truss, bolt, concrete, chair, computer monitor, etc. that was resting down through the buildings. Why then, considering the mass did NOT increase in some linear 1 + 1 + 1 fashion, do we see the collapses hurtling downwards at a smooth, unrelenting pace, so easily and uniform?



posted on Oct, 18 2006 @ 11:15 PM
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Originally posted by bsbray11

Originally posted by Pepperslappy
I have to say though. If the building collapsed on itself wouldnt the vellocity not be constant?


EXACTLY.

It should have slowed down or sped up or something. People who think the mass simply built up more and more should have be wondering why there wasn't positive acceleration. People who know better and realize that 80+% of the masses were ejected out of the footprints should be wondering why they did not slow down as the resistance increased.

Either way, work is being done. The initial falling mass only had so much potential energy, and it was working upon a body that was provided (or SHOULD have been providing) constant resistance for every column, truss, bolt, concrete, chair, computer monitor, etc. that was resting down through the buildings. Why then, considering the mass did NOT increase in some linear 1 + 1 + 1 fashion, do we see the collapses hurtling downwards at a smooth, unrelenting pace, so easily and uniform?


Exactly, I don't like pushing my ideas but if you notice. In every recorded building collapse the velocity was not constant. In every recorded modern day controlled demo, the velocity was unchanged or changed very slightly.







 
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