Originally posted by Damocles
so i guess what i meant by oversimplified was that most people arent taking all of the variables into account
You don't have to if there's a demonstrable and verifiable problem with only one of them.
This could be the "x-component" of the momentum of the ejected debris as the towers collapsed. For example, ~80% of the mass landing outside of the
footprints means an average of ~80% of the mass of each "floor" division of the building was ejected with a horizontal momentum component all during
the collapse. That
, in turn, means that only an average of ~20% of the mass of each floor was actually going downwards, ultimately.
It doesn't really matter where how much mass was and when, because the further more mass goes down, the less and less likely it is to end up
of the footprint without more and more significant amounts of energy being applied to it to increase its acceleration to the
appropriate value before it just hits the ground and comes to a halt. For example, you would have to apply a LOT of energy to a perimeter column on
the ground floor to send it out 30 feet laterally from the base, compared to a perimeter column 50 floors higher, because the perimeter column 50
floors higher would have a lesser acceleration as it slowly moved horizontally outwards 30 feet.
So, trying to keep all of the mass until the very last second doesn't work, either, if it comes across anyone's mind to suggest it as a problem. I
also assume the 20% of the mass that wasn't ejected actually went straight down and transferred all of its energy like it would have to, but I don't
know that it actually would. The geometry of the building itself would probably prevent anywhere near a 100% efficient transfer of shock load
straight down, even on the individual trusses.
So the question becomes, could 20% of the total PE that was released destroy almost 100% of a tower's welds and connections, an entire structure?
The initial amount of PE that was released in the first place was equivalent to masses only small fractions of the entire buildings anyway, and made
of the exact same materials. For WTC1, about 13 floors "fell" onto the 97 below, and never slowed down the whole time we could see it. This stuff
is why I think the towers were demolished. In terms of basic physics concepts, this stuff makes NO SENSE otherwise.
[edit on 21-12-2007 by bsbray11]