911 physics for dummies

[chris lz]

Perhaps this belongs in Sizzler’s recent thread. While there’s some overlap, I didn’t find exactly what I’m looking for (maybe I didn't look hard enough). Nor is my theme quite the same. Unlike Sizzler, I’ll state at the outset I’m not a truther by any stretch of the imagination (see Colboard.com) But for those with a pathetic physics background, I find in my debunking life I’m forced to rely on physics papers I can’t defend directly. So I'm curious, to what extent would the most basic physics claims supporting a “natural collapse” be accepted by all (or almost all) physicists? I'm confining myself to the twin towers for now. For instance, what formulas/calculations, etc., if shown to the average college level physics professor, would unhesitatingly be endorsed; and which ones (given by truthers) would be firmly rejected? Would they automatically reject Ross and Kuttler, in favor of Greening and Mackey, for example? Or might they be divided? The following are three all too common truther claims I'd like to look at in this regard:

1 As Prof. Jones likes to say, explosives were needed to “eliminate” or remove the mass to account for free fall/ almost free fall, every x floors.

2 -The twin towers fell into their own footprints (approximately, at least). And the related claim it took the path of “most resistance.” (comment: what would the path of most resistance actually be?)

3 -

burning steel pieces (weighing thousands of pounds) of the towers were hurled outward for hundreds of feet at speeds of about one hundred feet per second. . . . . The other reason for ignoring the details of the collapses was that certain troubling aspects, [i.e. like the above observation], would not need to be analyzed.

The above quote is from EugeneAxeman, one of the more sophisticated 911 skeptic posters I’ve read on the internet. Here are a few more of his specific claims:



4-

Calculations which took into account the energy consumption required to pulverize the buildings as observed show that the collapses took place at a rate over three times that which was possible by gravity alone.

(Where is he getting “over three times” from?)

5-

In reality, steel bends, and over 200 supporting columns, along with their cross-bracing would need to get out of the way at once to allow the upper section to fall.

6-

The physics I know tells me that when a building collapses, the energy is distributed across the surface area and the total mass of the falling section cannot be assumed to be focussed in a single point.

In fact, due to the inevitable fracturing and fragmenting suffered by the falling section, the collapse is better modelled as a series of interdependent impacts.

Kuttler simplified the model, but in the direction which would aid the gravity-driven presumption. Instead, it validated that the fall times were too fast, given the amount of material being destroyed by the collpase.

Less challenging, but still curious:

7-

I have access to several videos of the tower collapses, and they all show a characteristically high volumes of smoke being expelled from the buildings just prior to their vertical movement. The smoke is consistent with the color of aluminum oxide generated from thermite reactions

8-

The fires were not hot enough to weaken the steel to the point of failure, although efforts have been made to alter data and reality in order to meet that criteria

9-

Even the NIST investigators had to distort the data to create their model where collapse inititiation would occur. Their own lab tests failed to duplicate the condition where the steel would sag to the degree to which they claim took place

So, for 1-6 at least, are we dealing primarily with questions of elementary physics? Or does one really need to go more in depth? What would be your one favorite formula/calculation/etc (if any) to quote when replying to any of these truther claims? (And, for any skeptics, what would be your favorite one that you think would refute the "natural collapse" physics?)

Thanks for helping the science-challenged, and for putting up with potentially already-answered-a-thousand-times-questions.

Chris

 

[beachnut]

All of it is BS. You should try looking up some of them and answer some of them yourself.

Jones made up his ideas 4 years after 9/11. Sad, because he missed the real work and investigation done. So his stuff you can throw out because it is nut case stuff. But of course calling his stuff nut case makes me wrong. But waking up 4 years after 9/11 and making up thermite is NUTS.

Number 2 is funny! Their own footprint. But look at your number 3. You would think someone in 9/11 truth would not debunk the other truthy stuff! See the big problem? Which is is 2, or 3. I choose 9/11, what happen on 9/11, not the made up junk of 9/11 truth.

Number 4, is a drug induces idiot statement. The building was not turned into dust! Idiots make up real sad stuff. Believe me #4 has to be a drug induced statement of woo. The idiots make it up to fool idiots. Funny how that works.

Number 5, as steel bends with it gets hot, it fails to hold the load. There are hundreds of examples of failed steel structures bent and failing killing many people under them. Just bend and stand is a fairy tale for idiots. (have not heard the cross bracing for a while)

Number 6, model it how you want, you will get the same result. Number 6 is more BS from idiots.

7 is from NUTS, there was no thermite planted in the WTC Jones made it up 4 years after 9/11. The smoke was normal for a building fire. 4 years! Jones was asleep for 4 years, he is nuts.

8 - fires were hot enough to make the WTC fail. Darn, I hate it when history debunks the idiots! This is hearsay made up BS. Check it out. Fires with much less fuel have destroyed steel structures.

9 - NIST did models to check what happen on 9/11; You need to look up the goals of NIST before you even touch this one; you need to at least read what NIST had to do and why some of there experiments were done the way they were done. 10,000 plus pages of NIST! But you can find the goals easy.

9/11 truth does not use physics, they make up lies. They can not even get the story straight, look at 2 and 3. It has been 6 years; why are the lies still being repeated.

How can you just find 9/11 truth JUNK, where are some fact based ideas?

 

[FramerDave]

The "path of most resistance" in this case happens to be down. Exactly the direction in which gravity works. Do we really need to make it any more complex than that?

The smoke is consistent with the color of aluminum oxide generated from thermite reactions

Ok, assume the color really is the same as that produced from a thermite reaction. Answer this: Is there any other reaction type or fuel source which might produce the same color smoke? Any at all?

 

[Sizzler]

What got me skeptical was this.

9.2 free fall in a vacuum.

~11 seconds with air resistance

~15 seconds with all the steel and building contents.

so.

air slowed it down by ~20%

where as all the steel slowed it down by ~40%

So when I look at those two ~percentages, I found (and to a lesser degree still find it) hard to imagine that all that steel only offered double the resistance of air.

However the engineers here have showed me that this is expected.

 

[beachnut]

What got me skeptical was this.

9.2 free fall in a vacuum.

~11 seconds with air resistance

~15 seconds with all the steel and building contents.

so.

air slowed it down by ~20%

where as all the steel slowed it down by ~40%

So when I look at those two ~percentages, I found (and to a lesser degree still find it) hard to imagine that all that steel only offered double the resistance of air.

However the engineers here have showed me that this is expected.

Where did you get 11 seconds with air? Show me the work now? Source?

 

[Sizzler]

Where did you get 11 seconds with air? Show me the work now? Source?

I asked the question in my thread.

~11 seconds was the answer.

Because you annoy me, go find it yourself.

 

[beachnut]

I asked the question in my thread.

~11 seconds was the answer.

Because you annoy me, go find it yourself.

 

[chris lz]

All of it is BS. You should try looking up some of them and answer some of them yourself.

I certainly have. But it's rarely spelled out in such a way that a layman can understand easily. pp2-4 of the Benson Greening Bazant paper contain the most specific info I've seen on the basic collapse mechanism, but I still have trouble with it, not even knwoing much about many of the basic definitions you guys would.

How can you just find 9/11 truth JUNK, where are some fact based ideas?

I'm not understanding you. I only find Junk? I'm well aware of the science on both sides, as already indicated.

 

[chris lz]

The "path of most resistance" in this case happens to be down. Exactly the direction in which gravity works. Do we really need to make it any more complex than that?

So the path of most resistance and least resistance are both down?

Ok, assume the color really is the same as that produced from a thermite reaction. Answer this: Is there any other reaction type or fuel source which might produce the same color smoke? Any at all?

I posted that question not so much because of the color question, but because of the claim "high volume of smoke." In any case, I probably should have left it out, as it's not terribly specific.

 

[Gravy]

I asked the question in my thread.

~11 seconds was the answer.

Because you annoy me, go find it yourself.

Did you also notice in that thread that 11 seconds was the approximate time from the roof of the building, not from the impact floors?

 

[Gravy]

So the path of most resistance and least resistance are both down?

Yes, because it would take more energy to move that mass laterally so that it could fall through the air. Think of it as being the path of least energy change.

I posted that question not so much because of the color question, but because of the claim "high volume of smoke." In any case, I probably should have left it out, as it's not terribly specific.

As with most of the statements you posted, the observation is simply wrong. There was no large volume of smoke expelled sideways before the collapses began, nor were there any detonations.

When dealing with truthers, before you go about investigating what caused an event they're questioning, you need to determine if that event happened at all.

 

[chris lz]

Number 2 is funny! Their own footprint. But look at your number 3. You would think someone in 9/11 truth would not debunk the other truthy stuff! See the big problem?

Of course I see what you mean. But that's why I used the word "approximately." The towers did -more or less - fall straight down. Now I assume that's a pretty easy physics question to explain. I'm not saying otherwise. But the question of rapid debris ejection is more interesting.

 

[beachnut]

I certainly have. But it's rarely spelled out in such a way that a layman can understand easily. pp2-4 of the Benson Greening Bazant paper contain the most specific info I've seen on the basic collapse mechanism, but I still have trouble with it, not even knwoing much about many of the basic definitions you guys would.

I'm not understanding you. I only find Junk? I'm well aware of the science on both sides, as already indicated.

You found only false information; how did you just get 9/11 truth junk? Are you on purpose looking for the lies?

The paper you found is good. Take it and your fall time questions to your local physics teacher, and ask them for some help to protect you from the fraud of 9/11 junk science. The teacher or professor can give you some ideas.

Of course you have only scratched the surface, there are thousands of junk ideas from 9/11 truth.

 

[Sizzler]

Did you also notice in that thread that 11 seconds was the approximate time from the roof of the building, not from the impact floors?

right.

But 9.2 is from the roof to the ground.

So you are right, but 9.2 would be less too.

Right?

 

[chris lz]

Everyone, if you think this thread is totally ridiculous, let me know and I'll delete it (if I can.) My main purpose is, to what extent are the main physics claims elementary questions, and to what extent is it going to be confirmed by any physics professor picked at random? I honestly, after over a year of reading this stuff, don't know 100% for sure. Sure, I'm pretty convinced. But I'm going after the "100% sure." When I read the Greening paper mentioned, I struggle with the definitions and formulas. Please appreciate how someone with hardly any science background might look at that stuff.

 

[Gravy]

right.
But 9.2 is from the roof to the ground.
So you are right, but 9.2 would be less too.
Right?

Of course. As NIST points out, heavy items that did "free fall" from the collapse zones took about 9 seconds to hit the ground.

Sizzler, would you mind condensing your sentences? Your posts take up a lot of screen space for a few words.

 

[Sizzler]

Everyone, if you think this thread is totally ridiculous, let me know and I'll delete it (if I can.) My main purpose is, to what extent are the main physics claims elementary questions, and to what extent is it going to be confirmed by any physics professor picked at random? I honestly, after over a year of reading this stuff, don't know 100% for sure. Sure, I'm pretty convinced. But I'm going after the "100% sure." When I read the Greening paper mentioned, I struggle with the definitions and formulas. Please appreciate how someone with hardly any science background might look at that stuff.

Don't delete it.

I am more or less in the same position as you.

This is a good post for people working through all the claims, but don't have expertise.

 

[Sizzler]

Of course. As NIST points out, heavy items that did "free fall" from the collapse zones took about 9 seconds to hit the ground.

why did you use " " for free fall.

 

[Hokulele]

I certainly have. But it's rarely spelled out in such a way that a layman can understand easily. pp2-4 of the Benson Greening Bazant paper contain the most specific info I've seen on the basic collapse mechanism, but I still have trouble with it, not even knwoing much about many of the basic definitions you guys would.

One of the challenges with physics is that there are many situations that are not easily spelled out in such a way that a layman can understand them easily. Much of physics really is counter-intuitive unless you can do/have done the math (which is why some physicists can get a little testy when questioned). Here is a classic example of counter-intuitive physics.

http://www.physics.umd.edu/lecdem/services/demos/demosf3/f3-02.htm

There was a whole thread of these things posted here some time ago. I may try to go dig it up.

ETA: Found it.

http://www.internationalskeptics.com/forums/showthread.php?postid=2226771#post2226771

 

[beachnut]

Of course I see what you mean. But that's why I used the word "approximately." The towers did -more or less - fall straight down. Now I assume that's a pretty easy physics question to explain. I'm not saying otherwise. But the question of rapid debris ejection is more interesting.

The 2 acres of towers spread junk over 19 acres. Saying their own footprint is not exactly correct, it depends on which truther is telling you what. Some say too much was ejected due to bombs, some say it fell straight down like a CD. 2 and 3 are funny. The towers fell down like they did, in chaos, but just like expected; (so says the expert who built them).

He would be the best source, the guy who built them.

http://www.physicsclassroom.com/ some basic stuff to help understand if you have time