Hi Everyone, I'm pretty new to all of the debates and I can't claim to be any type of engineer. But I am trying to comprehend some of the physics here. I am college educated in business/accounting and took basic physics 101 as my science requirement. However, despite all the math that seems to flying around, I can't seem to get past some of the fundamentals being lost here.
The whole argument of free fall "collapse" seems very inconsequential to me. Whether 9 seconds, 12 seconds or even 15 seconds is determined to be "official" we seem to be overlooking many details. Even if we took the longest period of time of 15 seconds it seems impossible to me for gravity to be the only source of energy here. At 15 seconds and 90+ stories still standing, the rate of destruction is nearly 10 floors every 1.5 seconds. All 47 core columns and the multitude of exterior columns, which have always supported the weight and were overengineered, providing futile resistance is implausible. We're told to believe that 15% of the mass with a little help from gravity, can pulverize the remaining 85% of the mass. This flies in face of my very limited knowledge of physics. It also seems to be presumed that the top mass of the building is a solid object. The floors were open and spacious, I been in those buildings at least 2 dozen times on business. There isn't enough solid mass to keep pulverizing ALL of the building core and exterior columns, symmetrically, and in 15 seconds (im being very generous here with the times). Within 2 seconds of the collapse, the top portions is virtually disintegrated into the dust. I don't see any mass remaining 4 or 5 seconds into the "collapse" left to keep pulverizing the bottom third of the building. As improbable the collapse was in the first place, I would think it should have taken almost 90 seconds for that large of a building to fall. But SO utter and complete on top of it?
One point you make in your conclusion gurich that really puzzles me. You state "clearly the structure provided SIGNIFICANT resistance" to add a few mere seconds to the "collapse" time. But what confuses me, and maybe you could help explain for my own edification, is that if this is gravity collapse, doesn't fundamental physics tell us that it would fall through path of least resistance? Maybe free fall speed doesn't indicate CD, but symmetry does in my most meager and humble opinion. Lets say the planes took out a generous 10 core columns. There are 37 left. Even if heated to the point the point of buckling, which is doubtful and I'll point to the One Meridian Plaza fire which burned 19 hours and never collapsed, all of remaining columns had to of failed at once and straight down without bending. The South Tower tipped and should have kept tipping. If this was a gravity collapse, it should have just toppled right over, crumbling, falling apart, not pulverizing straight down. Steel beams hurled 500 ft across the street. Where does that energy come from? The Lobby (as seen in the Naudet bros film) was blown out. Where'd that come from? In that same seen, the Naudet brothers said there were people coming off the elevators on fire. How would jet fuel reach these folks in a hermetically sealed elevator system. Oh and be able to burn through the elevator cart? Had to be thermite reactions going off in the inner core to cause that.
Lastly, World Trade Center 7 was a controlled demolition. You have a better chance of winning the MegaMillions or Powerball Lotteries than a random collapse event that's never happened before or since to exhibit all the characteristics of CD. The proof is in FEMA's building performance report, Appendix C. I'll quote it, "Evidence of a high temperature corrosive ATTACK on the steel, including oxidation and sulfidation with subsequent intergranular melting... A liquid eutectic mixture containing primarily of iron, oxygen, and sulfur formed during this hot corrosive ATTACK. This sulfur rich liquid penetrated preferentially down grain boundries of the steel severely weakening the beam and making susceptible to erosion."
I know this isn't very scientific and excuse my poor attempt at applying what seems to me as common sense. But if it looks like a duck, quacks like a duck, then its a duck. Search google video for "this is an orange" and see if you believe your eyes or what you're told.
To TruthMod, My apologies if I made this too long. Thanks to all for reading.