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#121 |
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Banned
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Posts: 13,961
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#122 |
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Banned
Join Date: Jun 2009
Posts: 13,961
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Yes, I agree also. Even if it was 5 floors on a 10,000,000,000 story building. Built like the WTC, it would have collapsed to the ground. It would have taken about a week, but it would have happened.
I wonder if your doltish friends would still claim that it fell at freefall speed? |
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#123 |
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Banned
Join Date: Jun 2009
Posts: 13,961
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#124 |
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Banned
Join Date: Jun 2009
Posts: 13,961
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#125 |
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Penultimate Amazing
Join Date: Dec 2009
Posts: 18,641
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As most buildings are brick or concrete, I guess most demolitiojn techniques are mostly carried out on brick and concrete buildings.
However there really is no reason to assume it would not work just fine or even better on other kinds of structures. The basic idea remains: You initiate the demolition by taking out one story worth of supports. Top portion falls the height of one story. Picks up momentum through gravity. Force needed to arrest that momentun at next story far exceeds design loads. Next story fails and is added to the fall. Top portion plus one more story picks up even more speed. Thinking about it, I think verinage technique would work even better on steel frame. Reason: Most buildings involve reinforced concrete because that material is so much better at resisting bending and crushing forces. WTC was done in steel only because reinforced concrete would have been too heavy and massive at that height and would not have allowed the open office spaces. Therefore, steel represents a compromise at the cost of lower resistance to bending and crushing forces. |
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#126 |
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Penultimate Amazing
Join Date: May 2006
Posts: 11,494
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#127 |
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Penultimate Amazing
Join Date: Dec 2009
Posts: 18,641
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I kinda like the model.
However, I bolded the two problems (really only one) I have with it: 1. How long do you want the spaghetti to be? Standard Spaghetti are about 2mm wide and 300mm long (150:1) and weighs about 1g. A column of the twin towers would have a full length of over 432m from basement to roof. The perimeter columns were 36cmx36cm, giving them a ratio of length:width of 1200:1. The biggest core columns were 90x30cm - or width was 60cm on average - at the basement! Getting thinner towards the top. So standard spaghetti would be relatively too thick - but of course they are made of semolina and not of steel ^^ 2. How do you scale your model correctly, especially with regards to length:mass and length:load bearing capacity? I just did a simple measurement in my kitchen. I took one spaghetto* (is spaghetto the correct singular of spaghetti?), a good electronic kitchen scale, placed the spaghetto vertically on the scale (1g - but that is actually below the pecision of my scale; I weighed them by counting 20 and finding 20 of them weigh 19g). Then I pushed down on the spaghetto. Since it is not straight, it started bending right away. But it being flexible, I was able to put the equivalent of 30g on one specimen, 19g on another specimen and 22 on a third before they broke. Make that an average of 24g. They bent along their entire length, of course. No i introduced some lateral bracing near the middle of the spaghetto and measured again: This time I was able to place somewhere between 70 and 100g on top of one spaghetto without breaking it! Now suppose I divide my 300mm spaghetto into 110 pieces, each about 3mm long, and measure the weight a 3mm section of spaghetti can support; actually, that is hard to do (I am the kind of guy who was born with two left hands ). So ooookay I do it with 9mm (remember columns were stacked with individual sections spanning 3 stories): I could now put a weight of more than 300g on it, and it didn't break (due to my clumsiness, when I pressed harder, the piece would get snipped to the side).Now. 10% of 1 spaghetto weighs 0.1g one column section spanning 3 stories can support 300g (at least! possibly much more than that, I was just too clumsy to increase static load). That is 3000 times the column mass of the top 10%. You may add the mass of the floors. I am okay if you assume that the floors weigh 10 times as much as the columns; still your spaghetti columns can carry 300 times the weight of your top 10%. If you build your model to scale, your dimensions should be such that load bearing capacity of your spaghetti is only like 3-5 times the weight of your top 10%. You could achieve this correct scale by building the model with only 5 to 9 spaghetti but making the tower the mass of about 10 packs of spaghetti one pound (500g) each. I am fairly confident if your spaghetti-and-sugar-tower is thusly build to scale, it will crash all the way to the ground if you drop the top. * footnote: I actually did not use standard spaghetti but bavette, which differ from spaghetti by not being round but oval. Long diameter is 3mm and short diameter is 1mm - so by coincidence, they are 3x1 just like the core columns. |
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#128 |
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Philosopher
Join Date: Feb 2009
Posts: 8,408
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I envision the model being built to scale to around 6 feet tall so that the top of the lower block is at eye level. Then the top and lightest one-tenth of the structure is raised 12'' and dropped on the lower and more robust nine-tenths of the structure.l I invite the Readers to picture your ' crash all the way to the ground if you drop the top ' scenario
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*Think WTC7 - You cannot make the four corners of a table fall together unless you cut the four legs together *A kitchen table judgement on a world scale is enough * To Citizens: 'There comes a time when silence is betrayal' |
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#129 |
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Penultimate Amazing
Join Date: Dec 2008
Location: Central City, Colorado, USA
Posts: 10,587
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#130 |
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Penultimate Amazing
Join Date: Dec 2009
Posts: 18,641
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It's funny how you have, in 100% original truther fashion, completely dodged, ignored, missed the one important point of my previous post: That of scale. If you build your model 6ft (180cm) tall, that would be 6 spaghetti high, about 18 stories = levels of lateral bracing per spaghetto. Too bad I already ate my broken spaghetti, so I'll have to break another, make it 300mm/18 = about 16,5mm, measure the strength of that lenght of spaghetti... but at least with 6 spaghetti, you are now up to a height-thickness-ratio of 900:1, which is reasonably close to scale. *doing measurement on my kitchen scale* Oh! Bad news: 16.5 mm are a lot more easily to handle for a clumsy person like me! Turns out my first story-length piece (actually 17.5mm) of spaghetti supported at least 1100g before it broke. My second piece (16mm) was even stronger: I gave up when I peaked briefly a little above 3000g because my thumbtip hurt from the tip of the piece poking into it. Third piece (17mm) resisted 1500+g several times, where again I gave up as my thumb now seriously hurts. Dang, that spaghetti-stuff is strong! So by experiment one column of story-height can carry a static load of at least 1500g. Let's be conservative and say this is 5 times the actual load. Hence, let the top 10% (ohhh - can we make that 16.7%, so our top portion is as high as standard spaghetti are long?) weigh 300g per spaghetti column. As there are 522 columns, the total weight of the top block in our model would therefore have to have a mass of 522*300g = 156.6 kg. 522 spaghetti is coincidentally quite close to the number of spaghetti in a standard 1 pound (500g) pack that serves 4 to 5. So would a pack of spaghetti withstand 156.6 kg (twice my body weight) if it falls onto it? Hmmm. Let's further improve our model and calculations: I said that our spaghetti are laterally braced every 16.5mm - that is one story. Initially, our 156.6 kg would have to fall only those 16.5mm. What velocity will the upper block have? Let's see: potential energy U = m*g*h gets converted into kinetic energy Ek = 1/2 m*v2 m*g*h = 1/2 m*v2 <=> v2 = 2*g*h <=> v = sqrt(2*g*h) = sqrt(2 * 9.8m/s2 * 0.0165m) = 0.56 m/s Next step: The top block, falling at 0.56 m/s, falls onto our next set of 16.5mm long spaghetti, which excert a force up and will decelerate the block. At the same time, gravitation still pulls down (accelerate) at a rate of g. The movement cannot be stopped instantaneously in this universe, as that would be equivalent to an infinite acceleration and hence an infinite force. So as the falling block touches the tips of our spaghetti, the will get strained and bent. How much can you bend a spaghetto before it breaks? Next experiment: I bent a bavetta (a relative of the spaghetti family, see footnote in my previous port; mine are 257mm long) carefully in roughly a circular shape. Needless to say, the thing broke before it had formed a full circle, but it went round more than 180°. I am doing this in a very clumsy fashion - my best estimate is that I reached 240° of a circle, or 2/3 of a full circle. Full circle would have had a circumference of 257mm / (2/3) = 385mm. Radius therefore 385mm/2pi = 61mm. Now comes the tricky math part - if I bend an upright column piece of 16.5 into a radius of 61mm, it represents an angle A of (16.5mm/385mm)*360° = 15°. What is the distance hbent of the two ends of that column piece? *consulting my Bronstein-Semendjajev Pocket book of Mathematics* Aha! hbent = 2r * sin(A/2) = 2 * 61mm * sin(7.5°) = 15,924mm = 96.5% of column height. In other words: Our spaghetti columns of 16.5mm can elastically bend until the floor resting on them has moved down by 0.576mm = 0.000576m So if we want to stop the top floor's 0.56 m/s before the spaghetti break and the story collapses, deceleration to 0 has to occur within 0,576mm. Now, the formula to derive distance from acceleration is s(t) = 1/2 a*t2 = 0,000576m <=> t = sqrt(2 * 0,000576m / a) same for velocity vs. acceleration is v(t) = a*t = 0.56 m/s <=> t = 0.56 m/s / a so sqrt(2 * 0,000576m / a) = 0.56 m/s / a <=> 2 * 0,000576m / a = (0.56 m/s)2 / a2 <=> 2 * 0,000576m = (0.56 m/s)2 / a <=> a= (0.56 m/s)2 / (2 * 0,000576m) = 272 m/s2 = 27.8g Ok here is a problem: We said that our columns are designed to be able to carry 5 times the static load, that is, resist a force of 5g times the mass on top. However, we'd need columns that are nearly 6 times as strong! That means: Our spaghetti will break before the top mass has come to rest. Collapse will continue! Did we at least slow the fall somewhat? Sure, let's see by how much. Initial velocity (down) vi = 0.56 m/s Max. upward acceleration that our columns can bear is a = -5g = 49 m/s2 But this -5g is diminished by the constant pull of gravity, so our spaghetti can effectively decelerate the falling mass by a = -4g = -39,2m/s2 Velocity is v(t) = vi - 39.2m/s2 * t Distance (fallen) is s(t) = vi*t - 1/2 39.2m/s2 I am too lazy now to figure out analytically at what t s(t) >= 0,000576m and what v(t) is then. I quickly ran the formulas through a spreadsheet: t v s 0,0000 0,5600 0,000000 0,0001 0,5561 0,000056 0,0002 0,5522 0,000111 0,0003 0,5482 0,000166 0,0004 0,5443 0,000221 0,0005 0,5404 0,000275 0,0006 0,5365 0,000329 0,0007 0,5326 0,000382 0,0008 0,5286 0,000435 0,0009 0,5247 0,000488 0,0010 0,5208 0,000540 0,0011 0,5169 0,000592 So we see: After only 0.0011s, we have exceeded the maximum elastic deformation our spaghetti can bear, at which pint they break. Velocity is then still 0.5169m/s, or 92% of the initial 0.56m/s Our accumulated stories can now fall more or less freely for 15.96mm, during which velocity increases to about 0.7609m/s. Then we have another spaghetti crash which will again reduce velocity by only about 8% etc. etc. Result: We can expect our 6' tower with 522 spaghetti columns and a total mass of 939.6kg to collapse within 10% of free fall speed |
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#131 |
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Philosopher
Join Date: Feb 2009
Posts: 8,408
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'm sure that's all very very interesting and the Readers can read it if they want. But I am appealing to people's personal experience and intuition here. To what they know in their bones. And I believe that they know in their bones that one tenth of an object will never crush nine tenths of the same structure down flat on the ground by gravity alone as we saw on 9/11.
You can maybe convince a few Readers by here and now describing a documented event in the entire recorded history of this planet where one-tenth of any object, large or small has crushed the other nine-tenths of the same structure by gravity alone. For instance the collapse of the spagetti model will arrest almost immediately. It's intuitive you see ? |
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*Think WTC7 - You cannot make the four corners of a table fall together unless you cut the four legs together *A kitchen table judgement on a world scale is enough * To Citizens: 'There comes a time when silence is betrayal' |
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#132 |
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Penultimate Amazing
Join Date: Sep 2006
Posts: 21,050
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#133 |
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Skeptic not Atheist
Join Date: May 2007
Location: West of Northshore MA
Posts: 24,744
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I see Bill's still trying to sell the "truther" lie.
Bill, no one's buying. |
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"Remember that the goal of conspiracy rhetoric is to bog down the discussion, not to make progress toward a solution" Jay Windley "How many leaves on the seventh branch of the fourth tree?" is meaningless when you are in the wrong forest: ozeco41 |
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#134 |
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Philosopher
Join Date: Feb 2009
Posts: 8,408
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Then make with the countless other documented examples there must be if this can really happen. I am willing to accept examples from the entire recorded history of planet Earth of any pther of millions of different types of structure where the top one tenth has crushed the other nine-tenths of the same object by gravity alone.
Let's face it....if you cannot do this simple thing then we have no reason to believe that it can happen at all except in a managed way like the deliberate demolitions on 9/11. |
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*Think WTC7 - You cannot make the four corners of a table fall together unless you cut the four legs together *A kitchen table judgement on a world scale is enough * To Citizens: 'There comes a time when silence is betrayal' |
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#135 |
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Penultimate Amazing
Join Date: Sep 2006
Posts: 21,050
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#136 |
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Skeptic not Atheist
Join Date: May 2007
Location: West of Northshore MA
Posts: 24,744
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__________________
"Remember that the goal of conspiracy rhetoric is to bog down the discussion, not to make progress toward a solution" Jay Windley "How many leaves on the seventh branch of the fourth tree?" is meaningless when you are in the wrong forest: ozeco41 |
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#137 |
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Penultimate Amazing
Join Date: Dec 2009
Posts: 18,641
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I was bored to reply, I took Bill's spaghetti tower with enthusiasm and made it into a valid to-scale model. Unfortunately, Bill seems to not be interested in the model he himself proposed, at least he ignores the specifics (experimental strength of spaghetti columns, required static load per story to scale correctly) and the work and the results.
![]() Kinda reminds of.... urrr.... well, the 9/11-Truth-Movement comes to mind: Ridiculous models, no interest in details if they have to do with basic physics, moving goal posts, hand-waving, ignorance, arguments from imagination (or lack thereof), ... |
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#138 |
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Penultimate Amazing
Join Date: Sep 2006
Posts: 21,050
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#139 |
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Skeptic not Atheist
Join Date: May 2007
Location: West of Northshore MA
Posts: 24,744
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__________________
"Remember that the goal of conspiracy rhetoric is to bog down the discussion, not to make progress toward a solution" Jay Windley "How many leaves on the seventh branch of the fourth tree?" is meaningless when you are in the wrong forest: ozeco41 |
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#140 |
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Philosopher
Join Date: Feb 2009
Posts: 8,408
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__________________
*Think WTC7 - You cannot make the four corners of a table fall together unless you cut the four legs together *A kitchen table judgement on a world scale is enough * To Citizens: 'There comes a time when silence is betrayal' |
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#141 |
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Suspended
Join Date: Aug 2007
Location: Sacramento
Posts: 60,126
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I see bill smith has not changed any in his/her abscence.
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#142 |
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Penultimate Amazing
Join Date: Dec 2009
Posts: 18,641
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Watch the verinage demolition videos once more, and while you do that and observe how story after story gets crushed by the top floors, ask yourself the same question.
Then consider the likelihood that the best conclusion is urrrr "inside job" or whatever it is you want to sell. And consider the possibility that you do not understand structural engineering and dynamic mechanics. |
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#143 |
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Penultimate Amazing
Join Date: Dec 2009
Posts: 18,641
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#144 |
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Philosopher
Join Date: Feb 2009
Posts: 8,408
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__________________
*Think WTC7 - You cannot make the four corners of a table fall together unless you cut the four legs together *A kitchen table judgement on a world scale is enough * To Citizens: 'There comes a time when silence is betrayal' |
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#145 |
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Penultimate Amazing
Join Date: Sep 2006
Posts: 21,050
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Nominations for the Language Award in Forum Community. Yours are on page 4.
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#146 |
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Penultimate Amazing
Join Date: Dec 2009
Posts: 18,641
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About as convincing as your previous post. Eh Readers?
Maybe, next time you want make a claim of your own, back it up with facts, list assumptions, do work and discuss results, insteaf of just flinging suggestive questions across the table? Would be a nice change - seeing a Truther do some real work and get it right. (Of course "getting it right" would be the same as you finding out that in fact both twin towers and spaghetti towers are doomed to total collapse once you allow one floor to fail completely.) |
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#147 |
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Philosopher
Join Date: Feb 2009
Posts: 8,408
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[Sigh]..Just answer the dang question if you dare...
' Oystein...when the top 13 floors fall onto the bottom 97 floors - is that a block of 13 floors dropping on an assembly of 97 single floors or is it an assembly of 13 single floors dropping on an assembly of 97 single floors ? ' |
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*Think WTC7 - You cannot make the four corners of a table fall together unless you cut the four legs together *A kitchen table judgement on a world scale is enough * To Citizens: 'There comes a time when silence is betrayal' |
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#148 |
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Penultimate Amazing
Join Date: May 2006
Posts: 11,494
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#149 |
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Penultimate Amazing
Join Date: Dec 2009
Posts: 18,641
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#150 |
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Penultimate Amazing
Join Date: May 2006
Posts: 11,494
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#151 |
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Penultimate Amazing
Join Date: Dec 2009
Posts: 18,641
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Ok - assembly dropping on assembly.
What's your point? The assembly of 13 single floors falls (picks up velocity, momentum) as a block. I guess the assembly consideration is not unimportant. However as long as the assembly is intact, it can push its momentum down on the next stuctural elements it hits. If the assembly comes apart, momentum is not acted against an parts keep falling. Crush-up occurs. You can't get away from the fact that once the top floors fall, the structure below must eat away all the momentum and kinetic energy, and will fail doing so. But I sense you want make a point here? Please make it! Improve on the way I modelled your spaghetti tower!
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#152 |
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Philosopher
Join Date: Feb 2009
Posts: 8,408
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__________________
*Think WTC7 - You cannot make the four corners of a table fall together unless you cut the four legs together *A kitchen table judgement on a world scale is enough * To Citizens: 'There comes a time when silence is betrayal' |
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#153 |
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I AM the Red Worm!
Join Date: Aug 2007
Posts: 4,452
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No you won't, Bill. You will offer nothing of substance, just continue to spout the same nonsense, and run from questions and points you can't answer.
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I'll be the best Congressman money can buy! As usual, he doesn't understand the relevant sciences, can't Google for the right thing, and appears to rely on the notion that a word salad liberally sprinkled with Google Croutons will make his argument seem coherent. -JayUtah |
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#154 |
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Philosopher
Join Date: Feb 2009
Posts: 8,408
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__________________
*Think WTC7 - You cannot make the four corners of a table fall together unless you cut the four legs together *A kitchen table judgement on a world scale is enough * To Citizens: 'There comes a time when silence is betrayal' |
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#155 |
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I AM the Red Worm!
Join Date: Aug 2007
Posts: 4,452
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Yeah, it will go exactly how I said it will go. Unless you plan to reveal yourself as a troll, and that you were stringing us along the whole time. That's the only thing I think you could possibly say that would give any of us pause.
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I'll be the best Congressman money can buy! As usual, he doesn't understand the relevant sciences, can't Google for the right thing, and appears to rely on the notion that a word salad liberally sprinkled with Google Croutons will make his argument seem coherent. -JayUtah |
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#156 |
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Philosophile
Join Date: Dec 2009
Location: Osaka, Japan
Posts: 35,116
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A Truther Replies...
Oh well, here goes with the response to Oystein's response ("glenn" is the Truther in question) :
Quote:
Quote:
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Слава Україні! **** Putin! |
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#157 | |||
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Penultimate Amazing
Join Date: Dec 2009
Posts: 18,641
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You are realling appealing to people's incredulity, lack of imagination and scientific laziness.
This is something they just cannot know in their bones, for their bones are so extremely tiny compared to the dimensions of the tallest buildings in the world. The dynamics therein utterly defy intuition. You dodge and ignore the examples we already provided, especially that of avalanches. I give you another: cardstacks. Watch what happens around 2:00:
It may be intuitive, but it's wrong. If people go only by intuition, they'd understand that the sun moves around the earth. And they'd be wrong. It takes more than intuition, namely some scientific rigor, to figure out that actually it is the spinning of the earth. But I am fairly certain that Readers' intuition will understand that 6 packs of spaghetti may carry a static load of a whopping 1 ton if you build your tower carefully, but will come down crashing wildly if you break enough pieces near the top, when the weight of 2 grown men starts falling. And that it will continue to crash because it gets the mass of 10 more grown men along the way. Cause you see, that would be the necessary mass for the model to be near scale. |
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#158 |
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Bandaged ice that stampedes inexpensively through a scribbled morning waving necessary ankles
Join Date: Jan 2007
Location: Cair Paravel, according to XKCD
Posts: 34,139
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__________________
There is truth and there are lies. - President Joseph R. Biden, January 20th, 2021 |
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#159 |
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Guest
Join Date: Jul 2007
Posts: 29,742
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"Uh huh. Do you usually have firemen hanging around like that when a demolition clearance is well underway? So these lance-cutter boys had rushed in (not bothering to clear a path), cut a bunch of core columns (why?), and rushed off again why firemen were still scratching their chins at the sight? Uh huh."
What an offensive argument from incredulity. Your friend appears completely unaware that is a cropped picture, and IIRC, you can see a crew working on another vertical beam in the background. And yes, the FDNY was at Ground zero. You might remind your "mate" that hundreds of FDNY firemen died at Ground Zero and were there throughout the recovery activity at the pile. |
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#160 |
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Philosophile
Join Date: Dec 2009
Location: Osaka, Japan
Posts: 35,116
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I'm not quite sure what he is talking about but I do have a few pictures here of clean-up crews working on the site which I would like to add to:
http://angrysoba.blogspot.com/2009_07_01_archive.html Do you know where I could find similar pictures which show the beams being cut? ---I should also have edited that part out of my mate's post because I don't want the focus to be on such easily distracting questions--- |
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Слава Україні! **** Putin! |
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