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Old 27th May 2006, 07:37 PM   #542
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Thanks, Gravy. I couldn't pass this one up.

Originally Posted by Mutton-Head View Post
A little physics.
Very little, as you will see.

An object falling to earth falls with a specific amount of force:
More accurately, a specific force causes an object to fall to earth. But ok, I'll let it slide.

The mass of the object multiplied by the acceleration due to gravity.

Mass x Acceleration = Force.
You've got Newton's 2nd Law right, but then you don't use it correctly. You remind me of my students who memorize the facts without understanding the underlying basis for them.

Think of this force as money in a bank account. You only have a specific amount that you can spend. No more.
I can't comment on this, as it doesn't make any sense at all to me. Use a force up? You might be thinking of energy.

It takes force to accelerate any object. Even a falling object.

When an object falls to earth, all of its potential energy is converted into kinetic energy. Its force (M x A = F) is used-up (spent) to accomplish this acceleration.
Stop right there. The force you are talking about is the gravitational force between the earth and the object. This is given by G*m*M/R^2, where m and M are the masses of the object and the earth respectively, R is the distance between the center of the object and the center of the earth, and G is a constant. This force exists all the time, regardless of where the object is or whether it is moving. Sitting on the ground, it experiences this force. Up in orbit, it experiences this force. In the next galaxy, it experiences this force, although by then it is admittedly extremely small. But at no time is this force "used up".

This is called free-fall. If any solid object is situated below this falling object, some of this “free-fall” force will be absorbed (used) (spent).
Again, I think you are confusing force with energy. They are two different concepts. Simply put, a force is a push or a pull. Energy is the ability to do work.

The fact that steel beams are flying outwards, means that the force of the falling floors is being absorbed. The force is being used to accelerate the steel beams away from the tower. It doesn’t matter how fast they are flying, or at what angle, straight out or not, etc… Just the fact that steel beams landed hundreds of feet from the tower, shows that force (from the falling floors) was used (spent). Force was also used to cut up the vertical steel beams.
Again, mistaking energy for force.

All of the structural steel was cut into pieces no larger than 30 feet long.
Much ado has been made lately that the steel beams broke into convenient 30-foot long sections, to be carried away by trucks. Assuming this is true (an assumption I'm not willing to admit to, but we'll stipulate for the moment) what is overlooked is that it those same beams were carried *in* by trucks when the building was constructed. If they have weak points, it would naturally be every 30 feet.

Remember, we’re talking about steel below the point of impact, which wasn’t subject to fire, and so was still structurally sound.
Structurally sound, perhaps, but certainly not designed to absorb the energy (energy, not force!) of the impact of the 30 or so stories above them.

Also, all of the concrete was turned into powder.
All? You mean to say *no* chunks of concrete survived?

This like-wise took force.
Energy. *sigh*

What we end up with, is an equation that doesn’t balance.

(The force of the falling floors) = (free falling floors) + (steel beams cut into pieces) + (steel beams thrown away from building) + (pulverized and powdered concrete)
Energy, energy, energy.

The falling floors do not have enough force to accomplish all of these things. We know this just from watching the video, because, as stated, the top floors fall at almost free-fall speed.
Energy. And how do you know they don't have enough? Where's the math?

(Not quite, but only a few seconds more. This is judged by comparing the falling tower with the falling debris.)
A few seconds more, and you discredit this? Many claim the towers fell in about 10 seconds. A few seconds more is 3-4. That's a margin of error of 30-40%!!! Heck, even opinion polls have margins of error of 1/10 of that, and that doesn't even deal with the exactness of the laws of physics.

Not only do the falling floors not have enough power to accomplish these four things, they don’t even have enough power to accomplish each of the last two (throwing beams, pulverizing concrete) individually.
I very much doubt you have performed the math necessary to make this statement honestly.

It doesn’t even matter if the steel at the top of the towers was turned into melted butter. The vertical beams at the middle and bottom of the tower would be intact. (No fire, no plane impact) (I’ve included a picture of the tower being built. Judge for yourself how much vertical steel went into its construction. Notice in particular the vertical beams in the center section. These were omitted/ignored in the NIST report.)
I take it you are a structural engineer, and are therefore qualified to make the above statement?

As an experiment, take a high-rise building, and drop it on a bunch of concrete. (Yes I know, we can’t actually perform this experiment.)
But a computer simulation can. Can anybody point us to one?

But I bet you would agree, the concrete would not turn to a fine powder.
I would not agree, as I am not a structural engineer. However, those with the appropriate expertise have said otherwise, and I trust that.

It would take more force than the mass of the building during free fall can supply.

As I said, the equation is way out of balance. If you add up the cost of:
1.) accelerating the top floors to free-fall speed
2.) cutting beams into pieces
3.) throwing beams out away from the building
4.) pulverizing the concrete (and everything else) to powder.
… You have a total that was more than we had in our bank account.
And you've done the math? Would you please present it?

The next step then, would be to find out where this extra force came from.

Explosives are the only plausible explanation that I can come up with.
And here's the underlying problem. Since that's the only explanation you, as a layperson, can come up with, that's the one you're convinced is correct. And you are the sort of person that once convinced, it doesn't matter how much evidence to the contrary is presented. You are the sort that, had Galileo offered you a peek through his telescope, you would have refused and then claimed that of course the Earth is the center of the universe, because there's no evidence to show otherwise.

This also would solve the problem that the building collapsed symmetrically in its own foot-print.
Perhaps you need to revisit the photographs of Manhattan. What about the debirs that hit WTC7, which you folks like to point out was several blocks away? What about the cloud that covered the lower half of the island? And if what you mean to say is that *most* of the debris fell straight down, well, where the h3ll else did you expect it to go? It would take a tremendous amount of...wait for topple a building sideways.

This has NEVER happened spontaneously, from a fire, or earthquake, or hurricane, or plane crash.
I don't know about this. But it's certainly a falsifiable claim. Can anyone out there provide just one circumstance where this *has* happened?

But we have seen it occur hundreds of times from controlled demolitions.
Dogs are furry with four legs, two ears, a wet nose and sharp teeth.
This animal exhibits all of those properties. Therefore it is a dog.
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Please excuse the excessive use of alliteration.
Alluding to alliteration is always amusing.
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