....
It doesn't matter which direction it collapses. Collapsing inwards doesn't magically remove the resistance of the internal infrastructure. Fire doesn't do that. Impact damage doesn't do that. I don't need precise measurements of every detail and qualifier you want to tack on for you to obfuscate that your theory requires the laws of physics to be violated. Gravitational acceleration, or "free fall" speed is approximately 32 ft/s2. Anything close to, at, or above that downward velocity REQUIRES zero resistance form internal infrastructure to be achievable under Newtons third law of motion. It is required, because if there was resistance, some of the energy held in the velocity of the downward acceleration would be lost in the destruction of the internal infrastructure as it fell, resulting in the slowing of its fall. ...
Actual written down math equations will always beat your blabber. You don't appear to even understand the matter, though. Here you go.
"Free fall" speed is not 32 ft/s2. That's the acceleration.
The speed may be considered as 32 ft/sec for the first second, 64 ft/sec for the 2nd section, and so forth. We're using 8th grade here, so no calculus. But it still works fine.
v (ft/sec) = 32(ft/sec2) * t(sec)
As the speed doubles, the kinetic energy quadruples.
e = 1/2*m*t^2
That "friction" that you keep harping about does not have to be zero. It could be a small amount, or a moderate amount. It's only in your head that it has to be zero. I repeat your assertion.
"It is required, because if there was resistance, some of the energy held in the velocity of the downward acceleration would be lost in the destruction of the internal infrastructure as it fell, resulting in the slowing of its fall. ..."Obviously, this "slowing of v" is trivial. It might have a significant effect on the 1st second. Say that is 1 second longer. It will then have 1/4 that effect on the 2nd second, 1/9 on the 3rd and so forth.
The series described is 1/2, 1/4, 1/9, 1/16, 1/25. That is the Basel problem, first solved in 1734. I confess to thinking it would be beyond 8th graders capabilities, and started to just suggest something less that 1.7 seconds.
But then I found this dude.
Ikhwan Mirza Hafiz
i'm 13 and i like maths and science.
https://www.quora.com/profile/Ikhwan-Mirza-Hafizeight graders are 12-14, I guess I can continue.
He showed the answer is pi squared / 6, or 1.644934066848.
What this means. Even with serious "friction", you will never have more than 1.64 seconds added to the descent time.
Thanks,
Spendy, for trying to confuse the issue with all kinds of junk that doesn't apply because it isn't enough of what really happened.
In order to get to near free-fall speeds in a building collapse, you have to remove the resistance. In the case of the towers, parts of them were actually falling way faster than free-fall. How do we know? Because it was the top of the tower that we base the free-fall speed on.
This means that the parts under the top,
which started to fall a whole lot later than the top,
would have to accelerate at far faster than gravitational acceleration,
which was already moving faster than the building under it that hadn't started falling yet,
so that those parts could get out of the way of the top,
to let it continue on down at free-fall speeds.
What is there than can cause parts of the building in the middle, to suddenly accelerate to faster than free-fall, just to get out of the way of the top which landed as though it fell at free-fall? Two things:
1. Demolition pushed the lower parts out of the way so the top could fall like free-fall (making them accelerate way faster than free-fall acceleration, btw);
2. The top was accelerated downward (by demolition) way faster than free-fall acceleration, so it could squash the lower parts that were trying to hinder its fall, fast enough so that it could take the whole thing down at free-fall speeds.
In other words, all the junk you said that I just quoted, helps to show that there was some kind of demolition or other force causing the buildings to fall, that was way greater than the force of gravity.