Potential energy

[westprog]

Sorry if this has been done before - but I haven't seen this particular analysis.

While reading the Judy Wood "Billiard Ball" paper, (the URL to which I am not allowed to post) I was struck by the following:

Looking at the data, we take the conservative approach that a falling floor initiates the fall of the one below, while itself becoming pulverized. In other words, when one floor impacts another, the small amount of kinetic energy from the falling floor is consumed (a) by pulverizing the floor and (b) by breaking free the next floor. In reality, there isn't enough kinetic energy to do either.

This is obviously very silly stuff, but it did stimulate me to try to calculate the kinetic energy involved in the collapse of one of the WTC buildings by one floor. This initially seemed a tricky calculation, but if it is done by calculating the difference in potential energy between the two positions, it's actually very simple.

I used the following values, all obtained from Wikipaedia, except for the weight. The weight of one of the WTC buildings has been a matter of dispute, but I've used the most commonly accepted value. I've used SI units - kilograms, metres and seconds.

Weight - 500,000 tonnes, or 500,000,000 kg
Height - 411 m
Number of floors - 110
Height of one floor - 3.7 m
Acceleration due to gravity - 9.8 m/s2

I've assumed that it's the top third of the building that is falling, so that gives

Effective weight - 166,666,666 kg


Using the formula for potential energy - mgh - we get
166,666,666 * 3.7 * 9.8 = 6,106,868,409 Joules

This being an impressive but not very meaningful number, I decided to give it in terms of tons of TNT. One ton (not tonne) of TNT releases 4,184,000,000 Joules when detonated. This gives us a value of 1.5 tons of TNT equivalent energy released when the top floors of the WTC drop one floor. This was described by Judy Wood as a small amount of energy.

It should be noted that the energy isn't all kinetic energy. Some of it will be expended crushing the contents of the floor that is collapsing, for example. But it will all have to be accounted for somehow.

I would be very grateful for any constructive criticism of the above calculations. They seem sound to me, but I might have missed something.

The main reason I've posted this is that it's a very easy calculation to make. All the information is publicly available. The potential energy formula is very easy. The more complex momentum analysis isn't needed. It's a simple matter of a vast amount of energy being released in a violent and uncontrolled fashion.

 

[R.Mackey]

Sorry if this has been done before - but I haven't seen this particular analysis.

While reading the Judy Wood "Billiard Ball" paper, (the URL to which I am not allowed to post) I was struck by the following:This being an impressive but not very meaningful number, I decided to give it in terms of tons of TNT. One ton (not tonne) of TNT releases 4,184,000,000 Joules when detonated. This gives us a value of 1.5 tons of TNT equivalent energy released when the top floors of the WTC drop one floor. This was described by Judy Wood as a small amount of energy.

I would be very grateful for any constructive criticism of the above calculations. They seem sound to me, but I might have missed something.

Hi westprog, and welcome.

Your numbers are right on track. I did a similar calculation some months ago, here, except instead of calculating the energy in dropping the upper block one floor, I calculated the total in the entire tower.

The only real weak point will be that the upper floors would have been less massive than the lower floors, so assuming a constant mass is rough, and will give you an answer that is probably a factor of 2 to 4 too high. I included such a correction in the footnotes of my post.

Still, we are indeed talking about a tremendous amount of energy. From Greening's whitepaper, the impact energy of the plane was about 750 kg TNT equivalent, and this was double the breaking energy of all the columns on one floor.

As for Judy Wood, she also argues that floors impacting other floors do so in an elastic fashion... and when falling floors hit floors below them, the lower floors begin falling from rest, as though the kinetic energy of the upper floors never existed. Her arguments need not be taken seriously.

P.S.: Boy, do I miss the Search function! Hope it's back up to strength soon...

 

[pvt1863]

Another problem with these analyses is that they always want to start from the top floor. In these models, the top floor falls on the second-to-top floor, which in turn falls onto the next floor and so on. In reality, the collapse of each tower was initiated at (or very near to) the impact point. This means that the first floor to be impacted by the collapsing region was struck with a very large part of the building. Calculating this energy is extremely difficult, however, since it cannot be assumed that the falling region acted as a rigid body.

The bottom line is that Wood's calculation is, in fact, not conservative because she assumes that only the energy available for initiation floor n's collapse is the kinetic energy from floor n+1. A truly conservative approach (from the standpoint of proving that the collapse speed was not possible) would have to assume that the energy from all the floors above floor n goes into collapsing that floor. When this is combined with the reality that a section of the building -- not a single floor -- collapsed initially, it creates a situation that cannot be dismissed with supposedly conservative hand-waiving.

 

[beachnut]

Sorry if this has been done before - but I haven't seen this particular analysis.


Using the formula for potential energy - mgh - we get
166,666,666 * 3.7 * 9.8 = 6,106,868,409 Joules

This being an impressive but not very meaningful number, I decided to give it in terms of tons of TNT. One ton (not tonne) of TNT releases 4,184,000,000 Joules when detonated. This gives us a value of 1.5 tons of TNT equivalent energy released when the top floors of the WTC drop one floor. This was described by Judy Wood as a small amount of energy.

It should be noted that the energy isn't all kinetic energy. Some of it will be expended crushing the contents of the floor that is collapsing, for example. But it will all have to be accounted for somehow.

I would be very grateful for any constructive criticism of the above calculations. They seem sound to me, but I might have missed something.

The main reason I've posted this is that it's a very easy calculation to make. All the information is publicly available. The potential energy formula is very easy. The more complex momentum analysis isn't needed. It's a simple matter of a vast amount of energy being released in a violent and uncontrolled fashion.

I was using PE = ghm also, and came up with 248 tons of TNT stored energy in each tower.

Judy Wood's work is not very good. She has moved on to a beam weapon because she can not do what you have done, think and use numbers.

She never mentions the things you did on your own. You should have the degree, she should be recalled to grade school.

 

[einsteen]

The potential energy stored is simply the total mass times the height of the centre of mass times g

 

[westprog]

Another problem with these analyses is that they always want to start from the top floor. In these models, the top floor falls on the second-to-top floor, which in turn falls onto the next floor and so on. In reality, the collapse of each tower was initiated at (or very near to) the impact point. This means that the first floor to be impacted by the collapsing region was struck with a very large part of the building. Calculating this energy is extremely difficult, however, since it cannot be assumed that the falling region acted as a rigid body.

The bottom line is that Wood's calculation is, in fact, not conservative because she assumes that only the energy available for initiation floor n's collapse is the kinetic energy from floor n+1. A truly conservative approach (from the standpoint of proving that the collapse speed was not possible) would have to assume that the energy from all the floors above floor n goes into collapsing that floor. When this is combined with the reality that a section of the building -- not a single floor -- collapsed initially, it creates a situation that cannot be dismissed with supposedly conservative hand-waiving.

The point I was trying to make was that once the top third/half/whatever of the building falls, the potential energy is converted into something else. Trying to figure out the breakdown exactly is hugely complex - but luckily it doesn't matter. The CT's discount everything - the pulverisation, the heat, the debris hurled to the side. But the energy has to be used up somehow. Judy Wood attempts to discount it totally - which is why she avoided quantifying it using the trivial calculation I gave.

 

[westprog]

The potential energy stored is simply the total mass times the height of the centre of mass times g

It should be noted that I haven't bothered to calculate the centre of mass. I've assumed that every point on the falling mass travels about the same distance - the height of one floor - and that seems to fit the observations.

 

[Anti-sophist]

I'd just like to point out that not only is Judy's model totally ridiculous, she still does the calculation completely wrong. In her graphs, treating each floor as a billiard ball, she doesn't do the collision time/order correctly. The most glaringly ridiculous conclusion to be found in her analysis is that, according to her, a column of billiard balls, the "100th floor" hits the ground first, and the "1st floor" hits the ground last. This conclusion is obviously completely wrong, even given the elastic model of collapse.

To clarify, she says the top floor hits the next floor, the top floor comes to a rest, then accelerates and hits the next floor. In her model the "top floor" is the floor which knocks every floor below it, each time stopping and reaccelerating. This is obviously wrong because the 99th floor would reach the 98th floor before the 100th would.

 

[westprog]

I'd just like to point out that not only is Judy's model totally ridiculous, she still does the calculation completely wrong. In her graphs, treating each floor as a billiard ball, she doesn't do the collision time/order correctly. The most glaringly ridiculous conclusion to be found in her analysis is that, according to her, a column of billiard balls, the "100th floor" hits the ground first, and the "1st floor" hits the ground last. This conclusion is obviously completely wrong, even given the elastic model of collapse.

To clarify, she says the top floor hits the next floor, the top floor comes to a rest, then accelerates and hits the next floor. In her model the "top floor" is the floor which knocks every floor below it, each time stopping and reaccelerating. This is obviously wrong because the 99th floor would reach the 98th floor before the 100th would.

AFAIAA, the Judy Wood Billiard Ball paper has never been amended, even to fix obvious errors like the above. It still has more appeal than Jones' freeze frame images of Thermite/Thermate/Termites. Judy Wood proves that the collapses VIOLATE THE LAWS OF PHYSICS!

 

[JonnyFive]

I like this kind of thinking, because it points out just how massive the forces involved in the collapse were. It wasn't like this was a minor event from a physical and mathematical standpoint.

When I see stuff like the chicken wire tower, I have to wonder if these people think buildings are magical and can do anything in the world without obeying the laws of physics.

 

[westprog]

Hi westprog, and welcome.

Your numbers are right on track. I did a similar calculation some months ago, except instead of calculating the energy in dropping the upper block one floor, I calculated the total in the entire tower.

The only real weak point will be that the upper floors would have been less massive than the lower floors, so assuming a constant mass is rough, and will give you an answer that is probably a factor of 2 to 4 too high. I included such a correction in the footnotes of my post.

Still, we are indeed talking about a tremendous amount of energy. From Greening's whitepaper, the impact energy of the plane was about 750 kg TNT equivalent, and this was double the breaking energy of all the columns on one floor.

As for Judy Wood, she also argues that floors impacting other floors do so in an elastic fashion... and when falling floors hit floors below them, the lower floors begin falling from rest, as though the kinetic energy of the upper floors never existed. Her arguments need not be taken seriously.

I figured that some of my numbers might well be out - but that's why I spelled out the way I did them. It's just a matter of correcting the figures and recalculating. Regardless, even if using the most conservative values, one ends up with a sufficiently huge energy value to explain all the observed phenomena.

I note the avoidance technique from the other thread. Sadly, giving the right numbers isn't enough. Judy Woods has no credibility as an analyst, but hers is the default CT viewpoint. Of course taken seriously it leads to energy beams from space and holographic planes.

 

[gumboot]

Just something to consider...

Most calculations are done for the upper mass falling one floor and hitting the next floor down.

However, as we know from the NIST report, collapse was initiated by exterior column failure across the entire impact zone, not by a single floor failure.

The floors inside the imact zone were sagging, and it can be assumed once the exterior walls failed, they would immediately all fall (it was the exterior walls preventing them failing).

So the initial collapse mechanism was for the upper floors to fall though ALL FLOORS in the impact zone. Now, of course all those floors in the impact zone would have hit the first intact floor MOMENTS BEFORE the upper floors did. So when the upper floors hit the intact floor, it had already been hit with EVERY FLOOR in the impact zone. This it's unlikely it was truely "intact".

I believe the mechanism for floor failure was just the floors. I imagine the trusses failing, collapsing onto each other, and pancaking down through the building, ahead of the "collapse line". This explains "squibs" down the building. It explains the eyewitness accounts of people who were in the building at the time of collapse but survived.

That essentially means, the only resistance the upper section was meeting was the exterior columns and the core. We can see in the collapse videos that the exterior columns peel away from the building in enormous sections, as the upper floors fall INSIDE the exterior columns.

Therefore the only thing the upper floors are actually impacting against is the core. I propose that the core, being much stronger, ripped the upper floors to pieces, and their disintegrating mass added to the general mass of material falling onto remaining floors. That also explains why the core remained standing for some time after the rest of the building had collapsed.

-Gumboot

 

[Trigood]

Hi westprog, and welcome.

Your numbers are right on track. I did a similar calculation some months ago, here, except instead of calculating the energy in dropping the upper block one floor, I calculated the total in the entire tower.

The only real weak point will be that the upper floors would have been less massive than the lower floors, so assuming a constant mass is rough, and will give you an answer that is probably a factor of 2 to 4 too high. I included such a correction in the footnotes of my post.

Still, we are indeed talking about a tremendous amount of energy. From Greening's whitepaper, the impact energy of the plane was about 750 kg TNT equivalent, and this was double the breaking energy of all the columns on one floor.

As for Judy Wood, she also argues that floors impacting other floors do so in an elastic fashion... and when falling floors hit floors below them, the lower floors begin falling from rest, as though the kinetic energy of the upper floors never existed. Her arguments need not be taken seriously.

P.S.: Boy, do I miss the Search function! Hope it's back up to strength soon...

R.Mackey,

I looked at the calculations in your post, and I had one question (otherwise I think I understand everything): Why do you use d (cross-sectional density of the tower, m/h) instead of just "m" in the integral? (My calculus is really rusty.)

Now, to address Westprog:

Your calculations seem accurate. However, I did a similar calculation a while back, and it was different a bit from yours. Instead of using h = the height of a floor, I used h = the height to the bottom of the "top portion" (above the impact zone) of each tower. That's the one thing I don't understand about your calculations, because isn't "h" supposed to be the height in the gravitational field, and therefore should somehow relate to the distance from 0 gravity (i.e. surface of the earth), not the height of an individual floor?

So, here's how I did my calculations: Assuming the top portion is 2/3 of the way up (as westprog did), I get a value of (rounding to two significant figures):

( (500,000,000 kg)/3 )* (9.8 m/s2) * (411 * 0.677 m) =
67,000,000 * 9.8 * 274 = 450,000,000,000 J =
~98,000 kilograms of TNT =
108 tons of TNT

http://www.convert-me.com/en/convert/energy

This is about 74 times what you got, Westprog (6.1 * 74 = ~450), which makes sense, because I am taking all 74 floors from the ground to the impact zone into account (i.e., the lower 2/3rds of the building), whereas you are just calculating for the height of one floor. (Tons of TNT convert also: your value of 1.5 * 74 = 111, about what I get.)

----

Now, to go back to R.Mackey's post, if you take my value of 98,000 kg of TNT in that top portion of the South Tower (this exercise relates much better to the ST where the impact zone was close to a third of the way down; not exactly, but a reasonable estimate for now).

In comparison to my value of 450 x 10[9] J, Mackey calculates 1010 x 10[9] J, which is in the same ballpark. Of course, he's calculating for the whole tower, whereas I'm calculating for the top portion only.

The sources of error in my value are (1) the tower got lighter with height (as Mackey pointed out), whereas I used the simplifying assumption that the tower had equal weight density through its entire height, and (2) I didn't integrate over the entire height of the top portion, but rather took its lowest point as my "h" value. (1) tends to make my value too large, whereas (2) tends to make my value too small, so it's hard to say which way my error will tend overall.

I'm having difficulties with your value for kilograms of TNT, R.Mackey. The energy conversion factor I found (http://www.convert-me.com/en/convert/energy) was 4612 Joules per gram of TNT, unlike your value of 4184. Where did you get your value? As a result, my calculated value of kg of TNT (98,000) for just the top portion of the towers exceeds your value (72,000) for the entire tower.

Then, as you say, we must apply a factor such as 30% to get that energy applied to the instantaneous breakup of the tower as it fell (although, as you point out in Note 3, the tower breaks up upon impact with the ground and itself and the kinetic energy dissipates as that energy of breakup and as heat, so less energy is lost than 70%, no doubt). [Actually, I find that whole part of your discussion confusing. The potential energy is used not just for breakup but is directly converted to kinetic energy that applies force to the building below. I'm a bit shakey on all this, so maybe I'll think about it some more.]

Anyway, I come up with a value of 0.30 * 98,000 = ~29,000 kg of TNT, for the value of the potential energy in the top of the South Tower available for "collapse alone," using that 30% analogy.

---

I'd like to go back to my original energy value of 450 x 10[9] J, or 98,000 kg of TNT, as I'm not at all convinced that all that energy isn't used in some way in the collapse (let's hash it out if you like). Anyway, all that energy is available for something, so it's significant, imho.

On another forum, to convey the huge magnitude of this energy, I converted it first to foot-pounds (an old British unit, I believe) and then to a unit I made up (ha), called "ton-miles," because it seems like an intuitive way to look at it:

450 x 10[9] Joules (http://www.convert-me.com/en/convert/energy)
= 331,900,000,000 foot-pounds ( / 2000 pounds/ton)
= 166,000,000 foot-(short) tons (http://www.convert-me.com/en/convert/length)
= ~31,000 mile-tons

To me, this conveys just as "graphically" as kilograms of TNT how much energy is involved in just the top portion of the South tower: Enough energy to push a ton of material for 31,000 miles, i.e., all the way around the equator of the earth, plus some.

To me, this value conveys well the INCREDIBLE amount of potential energy that became available for "work," as the tops of the towers came free from their bearings when their support structures failed.

Please help me correct any errors in calculation or logic that I've made. Especially since it took me a long time to write out this post and I'm pretty tired now!! Thanks!

Thanks, westprog, for starting this thread. I think the potential energy is one of the things that people have a hard time grasping (including me!)

 

[jaydeehess]

In a related issue I was approaching the idea of Hoffman's 90% energy deficit in the results of the collapse ofthe towers.


Hoffman does his calculations and comes up with an energy availability that is, in his calculations, only one-tenth that required to do what was shown to happen(in his view of what happened).

Ok, so then if there was only one tenth the energy required due to gravity AND the other 90% of the energy came from explosives then what are the calculations on the amount of explosives required to contribute 9 times as much energy than was available due to gravitational potential.

Hoffman states that 4 x 10^11 joules of energy would be available due to gravity. 9 times that is 36 x 10^11 joules.
TNT has 4.18 x 10^6 joules/Kg therefore it would require the equivalent to 861,244 kilograms(1,894,737 pounds) of TNT in addition to the gravity energy in order to do what Hoffman states happened.

Now C4 which is 18% more powerful that TNT would of course use less(C4 is 91% RDX) so that would be the equivalent of 1,605,709 pounds of C4(802 tons)

The premise is then that more than one million pounds of explosives were surreptiously installed in the steel and concrete of the WTC towers prior to 9/11. That dentonators and control devices were attached to the explosives as well. That these explosives were somehow protected from prior discovery, and premature destruction or detonation due to the plane impacts and subsequent fires, and that they all functioned perfectly on 9/11/01.

It is no wonder that Hoffman does not do these calculations and include it in his conclusions. Any scientific theory must be falsifiable. that is that it should stand up to other approaches to the same question. If Hoffman's calculations are correct then 1.6 million pounds of C4 or other explosives equivalent are required. However, such an amount being used brings up too many hard questions for Hoffman to bother with so he ignores it.

The number of trucks delivering goods to the towers daily is not quite valid. You would be unloading the entire contents of 25 - 35 large semi-trucks. Such would not be a normal sight and if smaller trucks were used then more of them would be required. It is simply unbelieveable IMHO that this activity would go completely unnoticed. Remember that this would not only have to be overlooked but be so invisible that no one has recalled such a level of activity even after the theories about planted bombs has come out.

So I condsidered mini-nukes but they would present many problems, and who says that a fusion bomb would not produce radioactive by products?
If all of the explosive power is contained in one device , where was it placed? Certainly not at the impact zones. It would have been very obvious for one thing and one would have to be able to pinpoint that zone before the planes hit and do so with +/- one floor accuracy. A nuke explosion would propagate at the speed of sound(or greater) but it takes sound a lot less time to travel the 1000 feet or so from the impact zone to the ground than even the 10 seconds we keep hearing about as the time it took to collapse the entire building. There is NO evidence of a supersonic shock wave travelling the length of the towers.


Then there is Gordon Ross, who in his paper states that ;
A considerable amount of energy would be required to pulverise the concrete into the fine
dust which was evident from the photographic and other evidence. To quantify this energy it is
necessary to use the fracture energy value, but this has a variable value dependent on, among
other factors, the size of the concrete piece, and its constituents, most notably, aggregate size.
There is no typical value. In order to assess the energy consumed I will refer to the work of Dr.
Frank Greening [2]. It should be noted that Dr. Greening, like Dr. Bazant, does not, as yet,
support the contention that the tower collapse was caused by anything other than the damage
caused by aircraft impact and subsequent and consequent fires. The tower, using Dr. Greening’s
figures, contained approximately 50000 tonnes of concrete, and the assumption is made that only
10% of this was pulverised to a size of 60 micrometres. One kilogram of concrete at this particle
size will have a surface area of 67 m2. We can now use Dr. Greening’s figure for concrete
fracture energy of 100J/m2 to show that the energy requirement for one floor would be
50*106kg / 110floors * 67m2 * 100J/m2 * 10% = - 304 MJ.

304MJ X 110 floors= 33400 MJ required to pulverise 10% of the concrete.

Using my figures above for the energy released by TNT that comes to a requirement of over 8000 Kg of TNT with 100% efficiency to do that job. That is still 8 tons. However, Pegalow and Fetzer comment that there were NO large chunks of concrete, that all of the concrete was pulverised, not just the 10% that Greening and Ross use. So we now need over 70 tons and that explosive power must still be utilised in such a way as to have all of its power go into the pulverisation of the concrete. Such a placement would require that these explosives be placed within the concrete and that their original purpose is indeed the pulverisation of the concrete. I can't think of why such a thing would be required by the architects of such a plot but let's ignore that for a while. If the explosives were 10 times as powerful as TNT we are back to 7 tons of it but if only 75% of the released power actually manages to go into the pulverisation of the concrete (I believe that I am being generous here) then we go back up to about 9 tonnes of explosives.

That is 9 tonnes of explosives, embedded throughout the concrete of the buildings installed and detonated in such a way(timing issues) as to allow the greatest use of its power in pulverising the concrete, not only on floors below but also those on and above the fire floors.

Hoffman or Ross, in either case one noticed anyone hammering holes in the floors to install several tonnes of explosives.

 

[R.Mackey]

R.Mackey,

I looked at the calculations in your post, and I had one question (otherwise I think I understand everything): Why do you use d (cross-sectional density of the tower, m/h) instead of just "m" in the integral? (My calculus is really rusty.)

I expressed it as an integral because that way we can use any arbitrary function for the tower density as a function of height. If you make the assumption that the tower is uniform density, you don't need an integral at all because it's trivial to figure out where the center of mass is. But if you don't, you need to calculate the center of mass, and it involves such an integral. See my footnote [2] in my original post.

I'm having difficulties with your value for kilograms of TNT, R.Mackey. The energy conversion factor I found (http://www.convert-me.com/en/convert/energy) was 4612 Joules per gram of TNT, unlike your value of 4184. Where did you get your value? As a result, my calculated value of kg of TNT (98,000) for just the top portion of the towers exceeds your value (72,000) for the entire tower.

As I referenced in my note [4] in my post, I got that value from Wikipedia. Our numbers are only about 11% apart, which is close enough for me. I have no opinion on whether your figure or mine is more correct.

Then, as you say, we must apply a factor such as 30% to get that energy applied to the instantaneous breakup of the tower as it fell.

You need to read the post in context. The "30%" factor was a suggestion by poster Mutton-head, one of yesteryear's conspiracy loons, who claimed that "only 30% would be available for pulverization since the rest was needed to accelerate the towers downward." Needless to say I don't agree with this at all -- I don't know how much energy was converted into pulverization while it was falling, and I don't know how to even estimate, since it was in the middle of an opaque cloud of debris and nothing can be seen. It also doesn't matter, since the "energy needed to accelerate" is a temporary cost. I think I've had to explain that to every single CT who's ever come here...

So anyway, ignore the 30%. It's mere speculation. I was merely humoring another poster, while showing that even if you only allow 30%, it's still a vast amount of energy.

At the end of the day, the total GPE I calculate assuming a constant density is 1.01 x 10¹² Joules, or about 240 tons TNT equivalent.

If I instead put in a linear density function, i.e. density as a function of height d(h) = d₀ (h_max - h), then you get a total of 6.67 x 10¹¹ Joules or 160 tons TNT equivalent. I can walk through this more carefully if you'd like, or you can tackle it on your own.

Now in your calculation you're considering the upper block only. Since the upper block is the highest, and you're assuming constant density, the upper block iss the highest energy density part of the tower. So I'm not surprised that your answer is nearly half of my total, despite the upper block containing fewer than half of the floors. Your numbers look correct to me, given the assumptions you used.

 

[jaydeehess]

BTW, saying that energy is 'used' or 'expended' is a misnomer. Energy cannot be destroyed or created. When energy is caused to bend a piece of steel that energy does not disappear. It is transferred to the surroundings, it can be in the form of sound as air molecules bump against each other carrying the energy outward or in the form of heat. When you bend a steel coat hanger back and forth it gets hot and it cools off by dissapating that heat to the surrounding air or through infrared radiation. That is the energy from of your muscles being transferred to the coat hanger's steel lattice.

In the case of the collapses a lot of energy was carried away in the sound of the collapse, in the diffuse kinetic motion of the dust and a lot of it was transferred to the ground as heat.

 

[R.Mackey]

In a related issue I was approaching the idea of Hoffman's 90% energy deficit in the results of the collapse ofthe towers.

Ok, so then if there was only one tenth the energy required due to gravity AND the other 90% of the energy came from explosives then what are the calculations on the amount of explosives required to contribute 9 times as much energy than was available due to gravitational potential.

The premise is then that more than one million pounds of explosives were surreptiously installed in the steel and concrete of the WTC towers prior to 9/11. That dentonators and control devices were attached to the explosives as well. That these explosives were somehow protected from prior discovery, and premature destruction or detonation due to the plane impacts and subsequent fires, and that they all functioned perfectly on 9/11/01.

Yup. Ridiculous, isn't it?

This is pretty much the same way I reasoned here. I only bring mine up because it includes a link to some kick-ass video...

 

[Wizard]

That also explains why the core remained standing for some time after the rest of the building had collapsed.

-Gumboot

Do you have any evidence that this is the case? If true, how did the core then disintegrate by itself?

 

[Pardalis]

If true, how did the core then disintegrate by itself?

I don't think it disintegrated, it crumbled because it didn't have anymore support (you know, the rest of the building) to keep it standing.

 

[Wizard]

I don't think it disintegrated, it crumbled because it didn't have anymore support (you know, the rest of the building) to keep it standing.

The core didn't need support, it WAS the support for the rest of the building. It was fixed to the bedrock and cross braced. If it remained standing after the collapse, what force caused it to crumble?