The physics of tower collapse part II

[Bushwacker]

Newton's laws can easily be used to show that all 3 WTC towers that fell fell far too quickly to have happened in the manner decribed in the Kean-Hamilton commission's report.

I happen to have great faith in mathematical proof. When you, or Dr. Wood, or whomever can show me some equations to go along with the theories, I will give them their due attention. I will also take a look through more of Judy Wood's material later, as I am currently at work and cannot give it the deserved attention at the moment. But when I have on the one hand 300+ year old accepted laws of physics with mathematical proof, and on the other hand some hypotheses which to my knowledge are not backed up with any quantifiable explanation of the WHAT Dr. Wood refers to, I have to go with the mathematical proof. This being for the very simple reason having nothing to do with malice or my mind being "trapped" or "brainwashed" or any such rubbish - I can readily understand and demonstrate:

-The laws of motion and gravity match the math.

-the laws of motion and gravity cannot match up with both the observed events AND the report of the events by NIST or the Kean-Hamilton Commission (particularly since the latter avoided WTC 7 entirely, but I digress).

If indeed Newton's laws can easily be used to show what you say then you had better do that, and achieve what no other truthseeker has yet done, despite the assertions we see here periodically.

Judy Wood is perfectly at home with normal proofs about the speed of destruction of the towers. see her very clear falling Billiard Ball model - which says the towers should have taken more like 90 - 100 seconds to fall. (Case 3)
http://www.drjudywood.com/articles/BBE/ ... Balls.html

Her billiard ball model has been pointed out to be farcially wrong ever since she posted it, since it ignores any transfer of momentum, ie she assumes each ball accelerates by gravity alone, despite being hit by the ball above. However, she has never corrected this obvious howler.

[marky 54]

theres a lot stuff promoted by j.woods and tv fakery npt etc, that is shockingly misleading.

it is hard to see how the errors could be missed or how certain conclusions can be drawn. i cannot hope feeling alot of it is delibrately misleading, ie: knowing it is wrong but promoting it to fool people anyway.

theres a world of difference between not understanding something, or disagreeing on the conclusions of the same evidence and purposily making up evidence that comes out of nowhere and is simply blatent lies.

[spiv]

Her billiard ball model has been pointed out to be farcially wrong ever since she posted it, since it ignores any transfer of momentum, ie she assumes each ball accelerates by gravity alone, despite being hit by the ball above. However, she has never corrected this obvious howler.

"Obvious howler"??

But surely Bushwacker, if a falling floor above hit a stationary floor below, and transferred some of its momentum to that floor, that should slow the velocity of the floor above. This is precisely what the conservation of momentum means. Look at Newton's Cradle, one steel ball will transfer ALL its momentum to another, and stop.

I suggest you study your "Basic Physics" a bit more, matey, and you would then realise why the laws of physics were being breached in the official 911 explanations.

[pepik]

I was going to make a remark about the truth movement and the conservation of stupidity but then I had second thoughts.

Spiv might want to note, however, that when the newton's cradle ball strikes the other balls, it is moving horizontally, i.e. it is not accelerating due to gravity any more. How does this compare to the vertical stacking of WTC floors?

[spiv]

Oh deary me Pepik, have you ever studied physics? Maybe you could answer your own question.

[pepik]

I have high school physics. How much have you studied?

[Bushwacker]

Her billiard ball model has been pointed out to be farcially wrong ever since she posted it, since it ignores any transfer of momentum, ie she assumes each ball accelerates by gravity alone, despite being hit by the ball above. However, she has never corrected this obvious howler.

"Obvious howler"??

But surely Bushwacker, if a falling floor above hit a stationary floor below, and transferred some of its momentum to that floor, that should slow the velocity of the floor above. This is precisely what the conservation of momentum means. Look at Newton's Cradle, one steel ball will transfer ALL its momentum to another, and stop.

I suggest you study your "Basic Physics" a bit more, matey, and you would then realise why the laws of physics were being breached in the official 911 explanations.

Yes, a very obvious howler. She assumes no momentum at all is transferred by the falling floor to the stationary one it hits, which is absurd. In Newton's Cradle, as you say, all the momentum is transferred, and the end ball swings up, without any acceleration from gravity, in fact the reverse. Dr Wood assumes no momentum is transferred and that the stationary floor accelerates only with gravity.

In the collapse of the towers, as you say, the falling upper floors were slowed by hitting the floors below, which is why the fall was slower than a free fall in air. They were not slowed much, because of the huge momentum they possessed, so the collapse was not much slower than free fall in air.

No one before managed to demonstrate the oft quoted statement that the laws of physics would be breached by the official explanation, are you going to have a go, or simply parrot it as a slogan? [/b]

[mr freedom]

Bushwacker, you may find this article of interest.

http://journalof911studies.com/articles/W7Kuttler.pdf

[sam]

But surely Bushwacker, if a falling floor above hit a stationary floor below, and transferred some of its momentum to that floor, that should slow the velocity of the floor above. This is precisely what the conservation of momentum means. Look at Newton's Cradle, one steel ball will transfer ALL its momentum to another, and stop.

I suggest you study your "Basic Physics" a bit more, matey, and you would then realise why the laws of physics were being breached in the official 911 explanations.

My bolding. "Slow the velocity" ?? What's that supposed to mean? Do you mean reduce the rate of acceleration? I suspect you know less about physics than you seem to be claiming.

The transfer of momentum will reduce the acceleration to less than that of a similar "object" falling unimpeded in air. Which is exactly what was seen on 9/11. Substantial pieces of WTC1+2 fell (off to the side) faster than the main collapse zone. As pointed out, that steel-ball desk toy transfers energy in the horizontal plane, not the vertical plane. Your analogy is not just poor, it's inadmissible.

So which laws of physics were, in your opinion, breached in the official explanation of the WTC collapses? I'm really interested to hear about it.

While you're at it, why haven't all those hostile physicists and engineers from Cuba, Iran, N Korea and the like published their works denouncing the 9/11 "impossible collapses" ? It's not as though the USA is without educated enemies. Why is it only nutters like Wood and Jones?

[mr freedom]

Sam, you may find this article of interest.

http://journalof911studies.com/articles/W7Kuttler.pdf

[Bushwacker]

Bushwacker, you may find this article of interest.

http://journalof911studies.com/articles/W7Kuttler.pdf

Mr Kuttler says of his work:
It was observed that the building (WTC7) collapsed in just 6.5 seconds. Could this possibly happen as a result of pancaking floors collapsing from the top down? We show here that if the collisions are inelastic, such a scenario is impossible.

Careful study of the videos of the collapse shows that actually it collapsed from the bottom up, not from the top down. This work is therefore of rather limited interest, as it is already generally accepted that if things were different, then they would not be the same.

[spiv]

The context of the question on this post was to do with conservation of momentum, and the equation for momentum is mass x velocity = momentum. Now imagine the situation a tiny fraction of a spilt second before the upper floor hit a lower floor (time = t and δt->0), and I mean a fraction of a second, such that we can, effectively for our purposes, ignore the effect of acceleration due to gravity. After all, momentum does not rely on gravity, it relies only on mass and velocity.

If m1 and m2 are the masses of the top and lower floors respectively, and v1 and 0 are the velocities of the upper and lower floors prior to impact, and v2 is the velocity of the two floors a split second after contact.

Prior to contact (m1 x v1) + (m2 x 0) = M where M is the combined momentum of the two floors.

The split second after impact, δt->0 and (m1 + m2 ) x v2 = M (momentum conserved)

So the momentum M equals both equations, therefore (m1 x v1) = (m1 + m2 ) x v2

As m1 + m2 > m1, it follows that v2 < v1, does it not?

[sam]

The context of the question on this post was to do with conservation of momentum, and the equation for momentum is mass x velocity = momentum. Now imagine the situation a tiny fraction of a spilt second before the upper floor hit a lower floor (time = t and δt->0), and I mean a fraction of a second, such that we can, effectively for our purposes, ignore the effect of acceleration due to gravity. After all, momentum does not rely on gravity, it relies only on mass and velocity.

If m1 and m2 are the masses of the top and lower floors respectively, and v1 and 0 are the velocities of the upper and lower floors prior to impact, and v2 is the velocity of the two floors a split second after contact.

Prior to contact (m1 x v1) + (m2 x 0) = M where M is the combined momentum of the two floors.

The split second after impact, δt->0 and (m1 + m2 ) x v2 = M (momentum conserved)

So the momentum M equals both equations, therefore (m1 x v1) = (m1 + m2 ) x v2

As m1 + m2 > m1, it follows that v2 < v1, does it not?

You've neatly proved that nothing can ever collapse, as collapses always slow down. Bravo.

I've highlighted the part where you went wrong. It's gravity alone that fuels this collapse. Without it there is no movement, no velocity, no momentum.

[pepik]

What is the ratio of M1 to M2? And what happens to this ratio as the collapse progresses?

[Alex_V]

If we were to totally ignore the effect of acceleration due to gravity, no collapse could ever even start.

I'm no mathematician, but surely your illustration of conservation of momentum actually shows how inevitable progressive collapse is once one floor has given way. The momentum conserved (presuming the floor doesn't halt the fall) will insure that a greater mass (m1) is starting at a greater velocity (v1) as it accelerates towards the next floor.

The great mistake (or deception) of the truth movement is in believing that the slowing that takes place after a floor is hit means that the collapse must eventually stop - a schoolboy error. v2 will almost certainly be less than v1, but as long as it is more than 0 (the velocity from which the initial collapse began) then it will be greater than v1 was by the time the increased mass hits the next floor. Basically your v1 and your m1 go up floor by floor, increasing the mass and velocity of the collapse.

On that basis, all that needs to be proven is that the first floor that the collapsing material hit gave way. After that collapse is inevitable on these terms.

[spiv]

Momentum does not rely on gravity, and don't forget δt->0. Study your physics fellas.

[Bushwacker]

Momentum does not rely on gravity, and don't forget δt->0. Study your physics fellas.

What actual point are you trying to make? No one doubts that V2<V1 in your example, but since V2>0 and the combined mass then accelerates downwards again, under the effect of gravity, V3, the velocity with which it impacts the next floor, >V1 and so on.

[mr freedom]

Bushwacker, you may find this article of interest.

http://journalof911studies.com/articles/W7Kuttler.pdf

Mr Kuttler says of his work:
It was observed that the building (WTC7) collapsed in just 6.5 seconds. Could this possibly happen as a result of pancaking floors collapsing from the top down? We show here that if the collisions are inelastic, such a scenario is impossible.

Careful study of the videos of the collapse shows that actually it collapsed from the bottom up, not from the top down. This work is therefore of rather limited interest, as it is already generally accepted that if things were different, then they would not be the same.

If the building collapsed from the "bottom up" as you say, it is hard to explain the collapse of the penthouse on the roof of the building, the disappearance of which occurs at the very start of the collapse. I think this is clear in all videos and therefore any "Careful study of the videos of the collapse".

[sam]

Momentum does not rely on gravity, and don't forget δt->0. Study your physics fellas.

My bolding. This is where your analysis is wrong.

In this case it does, as the top section is falling and the force of gravity is the only source of energy. No engines involved here.

[Bushwacker]

Bushwacker, you may find this article of interest.

http://journalof911studies.com/articles/W7Kuttler.pdf

Mr Kuttler says of his work:
It was observed that the building (WTC7) collapsed in just 6.5 seconds. Could this possibly happen as a result of pancaking floors collapsing from the top down? We show here that if the collisions are inelastic, such a scenario is impossible.

Careful study of the videos of the collapse shows that actually it collapsed from the bottom up, not from the top down. This work is therefore of rather limited interest, as it is already generally accepted that if things were different, then they would not be the same.

If the building collapsed from the "bottom up" as you say, it is hard to explain the collapse of the penthouse on the roof of the building, the disappearance of which occurs at the very start of the collapse. I think this is clear in all videos and therefore any "Careful study of the videos of the collapse".

Yes, the penthouse disappeared first, but Mr Kuttler does not mention that. Did pancaking floors collapse from the top down? If not, what relevance does Mr Kuttler's work have?

[mr freedom]

Mr Kuttler says of his work:
It was observed that the building (WTC7) collapsed in just 6.5 seconds. Could this possibly happen as a result of pancaking floors collapsing from the top down? We show here that if the collisions are inelastic, such a scenario is impossible.

Careful study of the videos of the collapse shows that actually it collapsed from the bottom up, not from the top down. This work is therefore of rather limited interest, as it is already generally accepted that if things were different, then they would not be the same.

If the building collapsed from the "bottom up" as you say, it is hard to explain the collapse of the penthouse on the roof of the building, the disappearance of which occurs at the very start of the collapse. I think this is clear in all videos and therefore any "Careful study of the videos of the collapse".

Yes, the penthouse disappeared first, but Mr Kuttler does not mention that. Did pancaking floors collapse from the top down? If not, what relevance does Mr Kuttler's work have?

Any rigorous approach to a collapse scenario has relivance, provides insight, comparison, and greater understanding. Kuttler himself does not seem to think it was a top-down pancake collapse. I imagine he chose this senario, with the (extremely aggressive) assumption,

Assume there is not support for any floor when it is hit by the collapsing floors from above.
Thus it is like the floor is just floating in the air when it is hit but it is stationary,

because it was a relatively straight forward calculation, and bias in favour of the official story (the assumption not necessarily the scenario). There does not appear to be an obvious collapse scenario to analyse (other than explosives).

[Bushwacker]

Mr Kuttler actually shows no signs whatsoever of acknowledging that it was not in fact a top down pancake collapse, either in his introduction, calculations or conclusions, rather he indicates that he thinks that was exactly what it was.

No doubt other relatively straightforward calculations could be made of scenarios that did not occur, and they would be of as little use as this woeful effort.

There is no bias towards a shorter collapse time in his assumption of a top down collapse, exactly the reverse, because the initial momentum he starts with is that of the top floor falling on to the one below, a single floor whose vertical velocity would be halved by the collision. In contrast, consider what actually happened: the entire building (less the penthouse) fell as more or less a solid body, a momentum 47 times greater. It encountered nothing else, but simply hit the ground and disintegrated, there was therefore no transfer of momentum. Ignoring air and crushing resistance, as Kuttler does, the top would be free-falling and would hit the ground in 6 seconds.

Producing work based on transfer of momentum when no such transfer took place is simply perverse, at best, and Kuttler's calculations have no value at all, as far as I can see.

[mr freedom]

Mr Kuttler actually shows no signs whatsoever of acknowledging that it was not in fact a top down pancake collapse, either in his introduction, calculations or conclusions, rather he indicates that he thinks that was exactly what it was.

No doubt other relatively straightforward calculations could be made of scenarios that did not occur, and they would be of as little use as this woeful effort.

There is no bias towards a shorter collapse time in his assumption of a top down collapse, exactly the reverse, because the initial momentum he starts with is that of the top floor falling on to the one below, a single floor whose vertical velocity would be halved by the collision. In contrast, consider what actually happened: the entire building (less the penthouse) fell as more or less a solid body, a momentum 47 times greater. It encountered nothing else, but simply hit the ground and disintegrated, there was therefore no transfer of momentum. Ignoring air and crushing resistance, as Kuttler does, the top would be free-falling and would hit the ground in 6 seconds.

Producing work based on transfer of momentum when no such transfer took place is simply perverse, at best, and Kuttler's calculations have no value at all, as far as I can see.

To be fair Bushwaker, Kuttler states:

The other possibility is that the building fell in such a way that the falling floors encountered very little resistance until they reached the bottom. This possibility seems more likely, especially when the videos of the building are observed

There is considerable bias towards a shorter collapse time in his assumption which I stated, and do so again,

Assume there is not support for any floor when it is hit by the collapsing floors from above. Thus it is like the floor is just floating in the air when it is hit but it is stationary.

In contrast, consider what actually happened: the entire building (less the penthouse) fell as more or less a solid body, a momentum 47 times greater. It encountered nothing else, but simply hit the ground and disintegrated, there was therefore no transfer of momentum. Ignoring air and crushing resistance, as Kuttler does, the top would be free-falling and would hit the ground in 6 seconds.

Yes, loosely speaking that is what we observe in the videos, the problem is explaining how such a scenario could occur. The building seems to instantaneously have complete and total loss of structural support, and falls like a whores draws, and disintegrates, it really is baffling.

[Bushwacker]

Yes, Kuttler does indeed say that, but I take that to be a disingenuous attempt to leave an opening for his friend Jones to come in and say that the reason for a lack of resistance was that key parts of the structure had been attacked with thermite, thermate, super nano thermate, or superduper imaginery thermate which might have been developed with convenient properties. Nowhere does he say that the building did not fall in a pancake collapse, starting from the top, the collapse mode he assumes for his calculations. Reading his paper with no other knowledge of the event, one would naturally draw the inference that a pancake collapse was what happened, and take his calculation at face value. At best, his omission to mention the actual collapse mode of the building was ill-advised, at worst it was dishonest.

I cannot agree that his model is biased towards a shorter collapse time, he starts with the momentum of a single floor, which builds up floor by floor until all the floors are moving, and they all move together only at the end. What actually happened was that they all started moving together, the maximum momentum achieved under Kuttler's model, and momentum was lost as floors were successively crushed. This is what happens in a controlled demolition, so it is not surprising that it should look similar or take a similar time.

However, you are correct in that what is difficult to understand about the collapse is not actually the time it takes, but why failure should take place apparently across most of the width of the building virtually at the same time. It was always considered that probably the unique design of the building was responsible in some way, and an article in a recent issue of Structure magazine, by someone who sounds like an informed insider to the NIST investigation, suggests a mechanism. LINK. This sounds like the best theory put forward to date.

[sam]

...
However, you are correct in that what is difficult to understand about the collapse is not actually the time it takes, but why failure should take place apparently across most of the width of the building virtually at the same time...

As a matter of interest, why do people assume that the entire structure went down in a synchronised lump in what is generally described as "global collapse" ?

The only thing visible in all the videos is the collapse of the external structure.

The early fall of the E Penthouse is absolute proof that a serious internal collapse was happening several seconds before "global collapse".

[Bushwacker]

...
However, you are correct in that what is difficult to understand about the collapse is not actually the time it takes, but why failure should take place apparently across most of the width of the building virtually at the same time...

As a matter of interest, why do people assume that the entire structure went down in a synchronised lump in what is generally described as "global collapse" ?

The only thing visible in all the videos is the collapse of the external structure.

The early fall of the E Penthouse is absolute proof that a serious internal collapse was happening several seconds before "global collapse".

Yes, you are quite right, and the internal collapse is a key point discussed by the author of the Structure magazine article.

[Dallas]

Her billiard ball model has been pointed out to be farcially wrong ever since she posted it, since it ignores any transfer of momentum, ie she assumes each ball accelerates by gravity alone, despite being hit by the ball above. However, she has never corrected this obvious howler.

"Obvious howler"??

But surely Bushwacker, if a falling floor above hit a stationary floor below, and transferred some of its momentum to that floor, that should slow the velocity of the floor above. This is precisely what the conservation of momentum means. Look at Newton's Cradle, one steel ball will transfer ALL its momentum to another, and stop.

This thread probably should have ended here, but I will read on.

[Dallas]

I was going to make a remark about the truth movement and the conservation of stupidity but then I had second thoughts.

Spiv might want to note, however, that when the newton's cradle ball strikes the other balls, it is moving horizontally, i.e. it is not accelerating due to gravity any more. How does this compare to the vertical stacking of WTC floors?

In theory, what should happen when floor A descends to strike floor B is the transfer of momentum, and acceleration instantaneously begins again due to gravity. Since momentum repeatedly is halved before the acceleration of gravity kicks in again, the result of this occuring several dozen times in sequence should not be a near-freefall speed collapse, but rather a considerably slower collapse process.

[Bushwacker]

I was going to make a remark about the truth movement and the conservation of stupidity but then I had second thoughts.

Spiv might want to note, however, that when the newton's cradle ball strikes the other balls, it is moving horizontally, i.e. it is not accelerating due to gravity any more. How does this compare to the vertical stacking of WTC floors?

In theory, what should happen when floor A descends to strike floor B is the transfer of momentum, and acceleration instantaneously begins again due to gravity. Since momentum repeatedly is halved before the acceleration of gravity kicks in again, the result of this occuring several dozen times in sequence should not be a near-freefall speed collapse, but rather a considerably slower collapse process.

You would be correct if the collapse started with the top floor, but with WTC1 the top 12 floors fell, so the momentum was multiplied by 12/13 not 1/2.

[Micpsi]

Dallas's remark still applies to the South Tower. But then you are notorious for cherry-picking those parts of an argument you can rebut and ignoring those that you cannot in order to create the illusion that your rebuttal is comprehensive, whereas it still misses the point, as it did here.