I am beginning to see a consipacy but it is not the same one as Acombfosho, in fact Acombfosho seems to be spreading this. Lots of this web material is farcical in it's analysis. I am not a structeral engineer but I can see a lot of the posts are using really bad science to support their claim - I suspect a few of these people are seeing these 9/11 events in a faith style belief like Acombfosho.
or even this simple experiment video which explains the basic laws of physics ?
I as mentioned earlier, this seems like a stupid experiment to me. In the real event 27 to 30 floors of the building fell onto the say 79th floor in their entirity and yet this man decides to make a tube to drop one ice cube, or concrete block, onto several others to model the effect. I would say a very obvious way to get a better model of the event is to drop 27 to 30 icecubes onto several below. This would still not be a great model but a great deal better than his. He seems to be a structural engineer and yet has gone to the trouble of demonstrating a silly model, I would say he wants to try to show his faith view and not try to use science in a reasonable way.
Please refer to Dr.Judy Wood's Billiard Ball Explaination
Here again somebody (I have no information on who Dr Judy is) is using science in a strange way with her pancake analysis. She shows several graphs of different scenarios and these, except perhaps the first freefall one, basically have no bearing on what happened.
Case 1, fine - she uses the fall from the top floor case where earlier I used the 80th floor drop, but there wont be a great deal in this as by the time you have collapsed 80 the mass is moving very fast probably 20 floors per second.
Case 2: I suggest this is done for effect. The time to drop 10 floors is
t = sqrt(2d/g)
each floor is about 3.9m.
t = sqrt(2*10*3.9/9.8) = 2.82s
I agree with this time but in this graph as can be seen the 100th floor starts from a zero velocity and it takes another 2.82s to reach and start the next. This is clearly rubbish, this 100th floor would not completely bring to rest the mass of the 10 previous floors and so the 90th floor would be hit sooner, starting somewhere in between the time for the blue and red line, I wouldn't be able to accurately guess where. By the time the 30th block is hit it has the mass of 30 floor hitting it pretty fast I would doubt it would slow the fall up by much at all and yet in this diagram it again comes to a complete rest and is given the 2.8s time to reach the next (???).
It is true the that way building are constructed the lower floors are stronger than the higher ones but this graph cannot be taken as any model of the way that the Twin Towers collapsed. It is put in only for effect to try to influence some people.
Case3:
Well what can I say exect even more extreme stupidity than case 2.
The time for one floor to collapse
t = sqrt(2*3.9/9.8) = 0.796s
This falls onto the floor beow momentarily comes to a standstill and then falls onto the floor below momentarily comes to a standstill.....
This is truely bizzare but has been put on the page to confuse. In this case the time to collapse is shown as 87 to 97.6s, in my reckoning it is 110 * 0.796 = 87.56s
I suspect the difference is that Dr Judy is using as slightly larger size for each floor.
Anyway, it is not a likely model of floor collapse in any way and so I wonder why this has been added to the web page.
Case4: Fine, if you want to get all the floors to collapse at freefall speed this is what you would do. (Or simultaneous if you didn't mind the lower floors getting to the ground first.)
It seems to me that the pancake collapse that ocurred does so in a is a very believable time. I would not personally be suprised at any time between from 10 seconds to 20 seconds. This Dr Judy web site has been dilliberately trying to make the case for an unbelievable collapse by showing very poor models and fancy graphs. An underhand approach and not science.
There are people that want to believe that some sinister agency aided the collapse but there appears to be very little chance of doing it after the Towers where hit, you would have to get some people in (persumably experts at demolition) up to the 70th+ floor and give them time to wire the building and get out. They would probably have to dress as firemen to avoid notice on the way up (I suspect it would take an age to go up that far against the flow of people) and down and also get them primed and briefed in the space of perhaps 1 hour. You may get away with such a plot for a Mission Impossible film but in real life this just simply can't be done.