Gravitatonal collapse of WTC buildings damaged by fire and newtons laws of momentum.

[rhys 0]

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>You seem quite happy to ignore Newton's laws of motion;

Are you saying the buildings went up or something?

The collapses were veritable demonstrations of the laws of motion.

I started this thread as not to hijack another, there seems to be a misrepresentation of the facts in regards to how the buildings fell 9 years ago today.

It is response to the incorrect statement by Billvon in the reply above.

This is an article by the person responsable for forcing NIST to admit freefall occurred in building 7. His work is extensive and I could/might post more of his work.

he is a professor and has studied these events extensively.

Once again I expect the bigoted and snark comments from the usual suspects and I dont expect them to have the intellect or courage to enter a reasonable discussion, I will do my utmost to ignore the comments from these narrow minded individuals.

There are however others that have the respect to post well thought out and presented comments, these are the people this thread is intended for.

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Destruction of the World Trade Center North
Tower and Fundamental Physics
By David Chandler

B.S., physics, Harvey Mudd College, Claremont, CA
M.A., education, Claremont Graduate University, Claremont, CA
M.S., mathematics, California Polytechnic University, Pomona, CA

Running Title: Downward Acceleration of WTC 1
Abstract

The roof line of the North Tower of the World Trade Center is shown to
have been in constant downward acceleration until it disappeared. A
downward acceleration of the falling upper block implies a downward net
force, which requires that the upward resistive force was less than the
weight of the block. Therefore the downward force exerted by the falling
block must also have been less than its weight. Since the lower section of
the building was designed to support several times the weight of the upper
block, the reduced force exerted by the falling block was insufficient to
crush the lower section of the building. Therefore the falling block could
not have acted as a "pile driver." The downward acceleration of the upper
block can be understood as a consequence of, not the cause of, the
disintegration of the lower section of the building.
Journal of 9/11 Studies - Feb 2010 2
Introduction
The destruction of the World Trade Center on September 11, 2001 was, by any assessment, a
momentous turning point in world affairs. More than eight years after the event, the causes of the
collapses of the three largest World Trade Center buildings (WTC 1, WTC 2, and WTC 7) remain hotly
contested despite official reports by government agencies, first by FEMA then by NIST, attempting to
lay the matter to rest...

The entire article with endnotes can be found here

"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

[jakee 1,489]

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Since the lower section of
the building was designed to support several times the weight of the upper
block, the reduced force exerted by the falling block was insufficient to
crush the lower section of the building.

Here's a fun experiment everyone can try at home.

Take a lumphammer and rest it on your toes. Are your toes crushed? No, your toes can support several times the weight of a lumphammer.

Now, take that same lumphammer and have someone drop it onto your toes from 10 feet up. Do they remain uncrushed?

Do you want to have an ideagasm?

[CanuckInUSA 0]

You just don't give up do you? Every time you come here, it's the same thing "It was a conspiracy, the USA purposely killed thousands of their own citizens". Should I direct you to the URL of the Communist Broadcasting Corporation's website? Otherwise known as Canada's beloved publicly funded CBC, the same Leftist media organization I exposed yesterday for their creative news editing all to serve up their propaganda to their loyal lemmings. There you will be in good company of "I hate America Canadians" who will lap up everything you have to say as the absolute truth.

You know in the years that it has taken to clean up ground zero, isn't it interesting how the workers never found debris consistent with what one would find in a controlled building demolition. No wiring, no crushed detonators, no evidence of chemical explosives. I guess the thousands of workers who cleaned up ground zero (some of whom might have had family members who died on that day) were also in on this great conspiracy of yours. Isn't it amazing after all these years not one of the people in on your great conspiracy came out and talked.

Has it ever occurred to you that people don't engage in "reasonable discussions" with you because they don't view you as someone who can even reason with logic? Keep peddling your conspiracy theories, but you will have more agreements if you actually migrated to websites where hard core "I hate America" Leftists are gathering today to spew their pure unadulterated hatred.

Try not to worry about the things you have no control over

[mccurley 1]

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requires that the upward resistive force was less than the
weight of the block

As the steel pan form used to creat the floor slabs, the columns, and the beams, and connections would have all been weakened by the fire, this would be true.

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Therefore the downward force exerted by the falling block must also have been less than its weight

Just think about this statement.
In what universe does the momentum of a falling object amount to less then its wieght?

The object in question being the upper block of the tower does not have a deceleration device, such as a parachute to slow it down.

If you can solve this one you can through away your parachute.

Watch my video Fat Women
http://www.youtube.com/watch?v=eRWkEky8GoI

[pbwing 0]

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Should I direct you to the URL of the Communist Broadcasting Corporation's website? Otherwise known as Canada's beloved publicly funded CBC...(blah, blah, blah)

Sure, what the hell...what is that URL. I've love to see where you 'exposed' the CBC...

[CanuckInUSA 0]

Here it is. But I don't think you have an open enough mind to accept this video:

http://www.youtube.com/watch?v=bDw5a0_iFBk&feature=related

Here is the response from the CBC after they were outed for spreading their propaganda:

http://www.youtube.com/watch?v=apctTk7ovWs&feature=related

Try not to worry about the things you have no control over

[rhys 0]

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You just don't give up do you? Every time you come here, it's the same thing "It was a conspiracy, the USA purposely killed thousands of their own citizens".

The USA (as a whole) did not do it, and the pepertrators are not limited to united states citizens. You can stretch what i am saying to any false statemtn you like, but the USA consistem of much much more thn a few crooks.

That is a feeble attemt to counter the truth.

How about you address the content or simply ignore it and refrain from posting.

You and your opinion are your own, not everybodies.

"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

[pbwing 0]

You have no idea of what I'm able to accept.

I accept that was a completely douchebag thing for the CBC to do. However, they were outed and they publicly apologized for it.

Do you know of any news agency that hasn't been accused and found to have distorted the news to suit whatever agenda they might have?

Personally, I could use a shake up at CBC. I can't stand Neil Macdonald - the chief Washington correspondent. He is far to anti American to be even remotely objective.

Are they left of center? Yes, of course - so is Canada. So are most new agencies. Do they distort news to suit their view of things? Absolutely, as many do.

Better yet, how many news agencies would publicly apologize for the misrepresentation. In regards to your other thread, it certainly wouldn't be Mr. Hannity (but that's right, he's not news, he entertainment....)

[rhys 0]

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Take a lumphammer and rest it on your toes. Are your toes crushed? No, your toes can support several times the weight of a lumphammer.

Now, take that same lumphammer and have someone drop it onto your toes from 10 feet up. Do they remain uncrushed?

a more realistic comparison would have the toe replaced with a slightly larger lumphammer.

Do the experiment again in this more realistic manner and see what happens.

"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

[CanuckInUSA 0]

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You have no idea of what I'm able to accept

Fair enough. I will take your word for it.

BTW ... the other thread is NOT my thread. I only participated in it saying "Don't trust anyone in the media until you have sought more than one source". So let's leave it at that. If we want to debate the media (which it sounds like we don't need to), we can meet in the other thread.

Try not to worry about the things you have no control over

[pbwing 0]

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If we want to debate the media (which it sounds like we don't need to), we can meet in the other thread.

Fuck it!! People hijack threads around here all the time.
I completely agree. I trust none of them.

Maybe we'll leave it at this. Sure - hate the CBC - God knows they deserve it sometimes....

But just be glad we live in one of the few countries where people can publically and freely challenge the new providers without fear of persecution and they in turn publically admit to their fuck ups!!

[rhys 0]

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Just think about this statement.
In what universe does the momentum of a falling object amount to less then its wieght?

The object in question being the upper block of the tower does not have a deceleration device, such as a parachute to slow it down.

If you can solve this one you can through away your parachute.

You could try reading the entire study rather than skinning my post, then you might have more os an understanding of what is being said.

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Explicitly invoking Newton's Third Law puts this result in another light. Since the forces in the
interaction are equal and opposite, the falling block exerts a force of only 36% of its weight on the
lower section of the building. In other words, as long as the falling block is accelerating downward we
have the counter-intuitive result that the force it exerts on the lower section of the building is
significantly less than its static weight. It is difficult to imagine how an upper block exerting a force of
only 36% of its static weight could crush the larger, stronger, undamaged lower section of the building
to the ground, when the building, at any level, was designed to support several times the weight above
it. Assuming a safety factor of between 3 and 5 [12], the observed acceleration implies that close to
90% of the strength of the lower section of the building must have been eliminated by forces other than
the supposed "pile driver," suggesting that some sort of controlled demolition was at work.
One might argue, in terms of the strength of the various elements, that the impact of the falling block
might crush the lower section of the building (although this assertion has been challenged [13]), but it
cannot crush the lower block while it maintains its downward acceleration. Prof. Graeme MacQueen
and Tony Szamboti have made a parallel observation, based on a similar measurement, in their paper,
"The Missing Jolt: A Simple Refutation of the NIST--Bazănt Collapse Hypothesis."[14] They point out
that any increased force on the lower section of the building must be accompanied by a decrease in the
momentum of the falling block. The transfer of momentum (which implies a loss of momentum for the
Journal of 9/11 Studies - Feb 2010 11
upper block) is what gives rise to the impulse. The falling block can lose momentum only to the extent
that it decelerates. It should therefore experience a "jolt" which we should be able to see in the video
analysis. But from the fact that the upper block continues to move downward without deceleration, it is
clear that there was no jolt despite the significant deformation of the building in the first three seconds.
The fact that a downward accelerating block would exert a force less than its own weight on the target
block may be difficult to accept intuitively, but that is because our experience suggests the target block
would resist the crushing blow. A rapidly moving hammer head driving a nail into a solid block of
wood typically exerts a force on the nail many times the weight of the hammer head. But that is true
only if the nail resists the blow. The large force that drives the nail into the wood is matched by a force
that simultaneously decelerates the hammer head, which is why multiple blows are typically required.
If, however, the nail is placed on a block of Styrofoam it will not significantly resist the blow. It will be
driven into the block with very little force. The falling hammer head will meet so little resistance that it
will be able to accelerate the whole time. In the case of WTC1, the falling block acts like the hammer
head driving the nail into Styrofoam, but, changing the picture a little, it is the interface between the
two blocks that is "soft." Something other than the falling block (explosives?) must be destroying the
structural integrity of the interface zone so that it offers only a small fraction of the resistance it was
designed to provide.

I am going to remove the sentences you pointed out so when they are read, they will be read in context.

"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

[Belgian_Draft 0]

David Chandler is not a professor. He is a high school physics teacher. A professsor is a senior teacher at a 2 or 4 year college or university. In some cases the term is reserved for department chair.
Real professors in this forum have told you time and again how you are wrong yet you choose to believe a high school physics teacher who is basing his theories on a poor understanding of physics.

HAMMER:
Originally employed as a weapon of war, the hammer nowadays is used as a
kind of divining rod to locate the most expensive parts adjacent the
object we are trying to hit.

[lawrocket 3]

Um - lower portions of the building DID weaken. The topmost floors of both towers stayed intact and fell when lower sections were weakened.

This Bull Shit in physics major perhaps should have an explanation of a couple things: (1) potential energy; and (2) kinetic energy. Thanks to gravity, all that matter piled up high is potential energy.

Now, the base floors of the structure were designed to be able to resist all that potential energy. However, when something like a plane hitting the building at 540 mph and spraying jet fuel that burns, well, the buiding has just absorbed quite a jolt of kinetic energy. (The plane was potential energy converted into potential).

Then, the part that was compromised was weakened to where it could not longer support the weight of the mass above it. All of that weight (potential energy) was converted into kinetic energy. So much kinetic energy, in fact, that seismometers as far as New Hampshire detected the shaking caused when the earth ultimately absorbed the impact.

Force? Weight? There is a relationship, but as we also know, kinetic energy is determined as .5(mass) x velocity (squared). When the top floors fell one floor it accelerated. The forces and kinetic energy increased on each floor below because more kinetic energy was hitting each subsequent floor (that energy being transfered DOWN) and we know it was transfered because the floors collapsed! They did NOT absorb the blows.

The author's assumptions about upward force are hilarious! Upward force (that against gravity) is "kinetic energy!" The kinetic energy was provided when the buildings were built!

A steel hand grenade is designed to withstand the energy of the incendiary substance within it, right? Well, it was support the POTENTIAL energy in it but the kinetic energy blows it to bits.

AND - the guy's thoughts that a 36% piece cn destroy the rest of it is similarly misreresented. His idea is fine assuming that the "block" beneath is solid. However, since the "block" is actually 80-90 or so separate floors (each individually collapsing under the top energy) then we see how farcical this is.

My wife is hotter than your wife.

[kelpdiver 2]

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This is an article by the person responsable for forcing NIST to admit freefall occurred in building 7.
...
The roof line of the North Tower of the World Trade Center is shown to have been in constant downward acceleration until it disappeared.

Rhys - these are not the same statements.

Freefall would be constant acceleration at 1g until terminal velocity is achieved. The second statement just says constant acceleration, though I doubt that this can be very accurately seen based on video replay.

[Kennedy 0]

That would be the "Hannity and Fox Liers" thread. There are several examples given thy show left leaning media fabricating stories just the same way right leaning ones are accused of doing.

witty subliminal message
Guard your honor, let your reputation fall where it will, and outlast the bastards.
1*

[jakee 1,489]

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Take a lumphammer and rest it on your toes. Are your toes crushed? No, your toes can support several times the weight of a lumphammer.

Now, take that same lumphammer and have someone drop it onto your toes from 10 feet up. Do they remain uncrushed?

a more realistic comparison would have the toe replaced with a slightly larger lumphammer.

Do the experiment again in this more realistic manner and see what happens.

No, seriously, try it my way.

Do you want to have an ideagasm?

[CanuckInUSA 0]

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Sure - hate the CBC

This may come as a shock, but I don't hate everyone at the CBC. Rex Murphy more often than not offers an honest "no shit" assessment to the current affairs and will speak out against anyone regardless of their politics who is not making sense. Plus I also think Nahlah Ayed is a woman who is not afraid to risk her life traveling to the world's troubled hot spots to report on the various conflicts and very much earns her CBC salary, and then some. Everyone else though at the CBC is pretty much useless (including Don Cherry who has gone senile) ...

Try not to worry about the things you have no control over

[billvon 2,991]

> It is difficult to imagine how an upper block exerting a force of
>only 36% of its static weight could crush the larger, stronger, undamaged
>lower section of the building to the ground, when the building, at
>any level, was designed to support several times the weight above
>it.

Agreed. It is easy, however, to understand that the dynamic load was several orders of magnitude greater than the static load, and thus caused basically instantaneous failure.

[rhys 0]

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Freefall would be constant acceleration at 1g until terminal velocity is achieved.

Freefall acceletation is what I intended to say, The buildings took 10 seconds, 10 seconda and 6 seconds respectivly.

As we know terminal velocity takes about 10 seconds for a human body to reach.

Are you tring to say it is impossible for something to freefall unless it makes it to termianl velocity?

hahaha!

"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

[Belgian_Draft 0]

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Freefall would be constant acceleration at 1g until terminal velocity is achieved.

Freefall acceletation is what was inteneded, The buildings took 10 seconds, 10 seconda and 6 seconds respectivly.

As we know terminal velocity takes about 10 seconds to reach.

Are you tring to say it is impossible for something to freefall unless it makes it totermianl velocity?

hahaha!

How could could think the poster was implying anything of the sort? There was nothing in the post to even suggest such a conclusion.

HAMMER:
Originally employed as a weapon of war, the hammer nowadays is used as a
kind of divining rod to locate the most expensive parts adjacent the
object we are trying to hit.

[skydiverkeith 1]

I won't waste my time with a rational response about the differences between theory and practical application.

I'm aware of this site's policy on personal attacks, but you sir, are a fucking moron. I hope you die after your airway is blocked by a pea that's, in theory, too small to suffocate you...

Blue skies,
Keith Medlock

[pchapman 279]

From the article:

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It is difficult to imagine how an upper block exerting a force of
only 36% of its static weight could crush the larger, stronger, undamaged lower section of the building
to the ground, when the building, at any level, was designed to support several times the weight above
it.

Lawrocket is right: One can't compare the building to a bunch of solid blocks. This isn't physics for pre-schoolers with their building blocks.

The point is that the falling stuff builds up some momentum when a floor of the structure collapses, before it hits the stuff below.

So that 36% thing is silly.

Compare to this scenario: Someone is trying to help me climb over a tall wall. I can stand on his shoulders and he can take the weight no problem. But I have to get higher, so he supports a 10' pole on his shoulder, and I shinny up it.

But I slip, and can barely hold on to the pole, supporting only 36% of my weight on the pole and thus on his shoulder. I accelerate downwards towards the guy helping me.

Wham! Big surprise, the truther guy at the bottom is mashed into the pavement. He can't believe I flattened him, as I was only exerting 36% of my weight as I fell... until I hit his shoulders...

[jakee 1,489]

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As we know terminal velocity takes about 10 seconds to reach.

Nice!

Do you want to have an ideagasm?

[Belgian_Draft 0]

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As we know terminal velocity takes about 10 seconds for a human body to reach.

What does that have to do with the WTC buildings?

HAMMER:
Originally employed as a weapon of war, the hammer nowadays is used as a
kind of divining rod to locate the most expensive parts adjacent the
object we are trying to hit.