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Reasonable doubt...All truthers(and whoever esle) please read

X said:
Assume I have a falling mass, and it hits something that resists the fall.
Assume that the mass was initially falling at 8 m/s/s. Assume that the resisting object can only resist with enough force to effect a (momentary) 5 m/s/s change on the acceleration of the first object.
Will the falling object decelerate?
No.
Its rate of acceleration will be reduced to 3 m/s/s, before returning to it's free-fall rate.
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Whoa there, tmd2_1 doesn't need any fancy fizziks or math, he's got TrutherSenseTM.
 
X said:
Why is it that so many truthers assume there must have been deceleration? It's like they view collision physics as a light switch. On or off. Accelerating or decelerating.

Why does it have to be deceleration?

Why do you not even mention the possibility or a reduction in the rate of acceleration?

Assume I have a falling mass, and it hits something that resists the fall.
Assume that the mass was initially falling at 8 m/s/s. Assume that the resisting object can only resist with enough force to effect a (momentary) 5 m/s/s change on the acceleration of the first object.
Will the falling object decelerate?
No.
Its rate of acceleration will be reduced to 3 m/s/s, before returning to it's free-fall rate.

No deceleration. Just acceleration. But reduced, momentarily.
Click to expand...

Because they confuse reduced acelleration with decelleration(negative acelleration)

Which brings up the question; "What is the smallest detectable change in acelleration possible in viewing a video?"

If the change in acelleration lasted less than 0.033 of a second then it may well be undectectable since it would only be in effect over the course of one frame of video.
Thus if the first floor pan failed in 33 milliseconds it is nigh on undectable.
A floor pan concrete was 4 inches thick plus the steel pan it was poured over and the trusses were a meter or less from top to bottom chord. Let's call it 1 meter thick in total.
If the upper section was falling at 90% g and fell through 3 meters the mass fell through the floor pan in approx 5 frames.
So theorectically IF one were able to measure the acelleration of the top section mass one might be able to see a change in the acelleration.
But wait,,, we are idealizing many aspects here;
- the top section is considered infinately stiff in all dimensions
of course it isn't, it will flex and distort at least a small amount confusing any measurement of acelleration.
- the top section is considered to have hit the lower section simultaneously accross its floor pan.
it would not have obviously, further confusing any precise measurement of acelleration.

Why?
Because acelleration is not directly observed. One can only measure position and time. The velocity of an object is taken to be the change in position between time intervals AND acelleration is the difference in velocity between subsequent intervals.
If you measure position every video frame you can get that position every 0.033 seconds. There will be an inherent error in the position measurement (+/- 0.x meters)
In simplistic error calculations;
You can therefore calculate average velocity over that 0.033 seconds and average acelleration over 0.066 seconds.

In determining average velocity between frames p2-p1=d1 v1=d1/t1 the margin of error of d is twice that of either p1 or p2. Do the same for p3-p2=d2 v2=d2/t2
Now we take v2-v1=delta v a=delta v/t2

Now let's break down a probable sequence of events from the idealistic scenarios.

Of course p1 would be the initial state of the tower before collapse so at the first frame after collapse initiation you can get an initial acelleration. It will fall for approx 25 frames of video before the upper section floor pan impacts the lower section floor pan.
BUT depending on where the columns failed (at floor level, halfway between floors, near the ceiling) the upper section columns will impact floor pans before the upper section floor pan reaches the lower section floor pan. In other words the effect of collission on acelleration will be spread out over this entire 25 frames before the two floor pans meet. thus perhaps a 0.9 g acelleration over this part of initial collapse.

The columns sections will easily punch through the floor pans further weakening them by fracture of concrete and steel before the upper section floor pan hits. This may or may not immediatly fail the lower section flor pan but probably will immediatly fail the upper section floor pan by lifting it off its seats.
Change in the roof line acelleration is minimal as the only energy used so far is to lift one floor off its seats and to punch holes in one floor pan.
Upper section continues down at essentially the same acelleration as before. column sections now reach the second lower section floor pan and punch holes in it while the second upper section floor pan reaches the other two. Given the degree of damage done to both of these floor pans, their trusses and truss seats, if the first lower section trusses and/or seats have not all failed, they do now. Probable that some area of flooring failed on first contact while others failed on second pan contact especially for the south tower.
Roofline acelleration, perimeter column acelleration of the top section is barely affected as failure is spread over several floors.

After a few levels all of the upper section has been converted to rubble but all this rubble, including some hefty steel core column parts, is moving very quickly now and thus exerting greater dynamic force on subsequent floor pans.

perimeter columns fail ahead of core columns but lag behind floor pan failures.


At least that's how I envision it.
Some people will however demand that tons of high explosives or thermite or unknown weaponry would have to be used.
 
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Look how hard bedunkers are trying to find a natural explanation for this. :D

Their trying means at least they recognize their problem. We can give them that. ;)
 
ergo said:
Look how hard bedunkers are trying to find a natural explanation for this. :D

Their trying means at least they recognize their problem. We can give them that. ;)
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I guess any math that you can't do on your fingers is "hard" in your world, eh ergo?
 
tmd2_1 said:
Already been done for me.

http://www.youtube.com/watch?v=ZjSd9wB55zk
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You are are proof of that. Your thinking has been done for you.


In the video you posted, David says, "Some calculus and basic physics required", but he uses that to make up nonsense. Why is David not published in a real journal on 911 issues?

David says this, which he makes up out of thin air, like Heiwa inspried; his delusional statement.
A small section of a structure, consisting of a few floors, cannot one-way crush-down a significantly larger lower section of same structure by gravity alone.
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The "small section" of the WTC? This is hilarious, the "small section" weighs over 29,000,000 pounds. A floor can only hold 29,000,000 pounds.

With over 14 floors above the impact zone, there are over 35,000,000 pounds, more than a floor can hold, and the entire WTC collapses because no floor can hold the "small section" falling down. David forgot to do the math that matters. And you say you don't need math, and you don't have to do the work, or check the work, the lies have been "done for" you.​

You posted a video with failed conclusions, made up out of thin air, not using math or physics. Yes he did use math and physics, but he makes up the conclusions. David failed, and he does your thinking for you.
​
 
I find it amazing they bother with this "jolt" stuff at all when apparently its all so "obvious" it was a demolition just by looking at the collapse.
 
tmd2_1 said:
No I'm talking about what was found on top of the building...not the whole WTC. 1/16th of an inch if you're not from the US (this is not an insult) it is very very small. Plus that building was 400 feet of the south tower the plane approached from the south west, so it was behind where it hit.

I don't appreciate you saying you have to dumb down anything. You have no idea what my background is, and I can assure you would be quite surprised. Let me give an example, if you take steam of any type of noticeable vapor and apply compression to it expands out. You take a solid object and it's outward expansion is much, much less. There's no reason for body parts to be hurled as projectiles that far out. Imagine your house falling on you, do you think you will disintegrate into fine pieces 1/16th of inch, and hurled 400 feet away. I know your house is not the world trade center, but it's the same principle. In fact look at the Kader toy factory collapse, a horrible collapse, but the wreckage is nothing like we see at the WTC. http://www.ilo.org/safework_bookshelf/english?content&nd=857170498 In fact I know of nothing that comes close to it nothing at all. Columns could have been "sprung" out because they were still attached to the floor below, causing the spring like action. But not humans.
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Several simple and very plausible causes have been pointed out to you. Your hand waving does not change those facts.
 
When somebody states they have academic credentials in a given subject, but refuses to detail those credentials, you can bet the farm that the credential they do have is from college...a barber college...or a universty... Hamburger University.
 
ergo said:
Look how hard bedunkers are trying to find a natural explanation for this. :D

Their trying means at least they recognize their problem. We can give them that. ;)
Click to expand...


Troofer projection. The natural explanations are easy to find, but trying to get willfully ignorant and terminally stupid troofers to understand such simple concepts is next to impossible.

On the other hand, troofers are constantly grasping and absurd causes...nanothermite, explosive ceiling tiles, holographic planes, etc.
 
Edx said:
I find it amazing they bother with this "jolt" stuff at all when apparently its all so "obvious" it was a demolition just by looking at the collapse.
Click to expand...

I suppose twoofers believe that you don't need to study to be a doctor,they just go to a guy who looks at said twoofer and gives an immediate one hundred percent correct diagnosis.
 
ergo said:
Look how hard bedunkers are trying to find a natural explanation for this. :D

Their trying means at least they recognize their problem. We can give them that. ;)
Click to expand...
You need to get a new act. You can't argue with facts, and being snide about things you are wrong on, like the US NAval Observatory and sundials, just makes you look bad.
 
jaydeehess said:
So you were wrong then. NIST clearly states that contaminants in the miz would be burning.
You were also wrong about pure aluminum as NIST points out the plane was aluminum alloy.
In addition, NIST indicates that there would be a slag on the surface of the material which according to you would include other contaminants.

Good on ya for debunking yourself, thank you.

The cup example is one in which the effect is exaggerated by the greater difference between force required to crush and force applied. The principle is the same, it too bad you cannot recognize that. In the case of the impact of upper towwer mass on the floor pans of the lowers section the dynamic force lower limit is approx 10X that which could be expected to be transferred via the trusses to the columns. LOWER LIMIT!

You also seem to have completely missed the fact that in BOTH towers the columns are NOT aligned at collapse initiation. They cannot be unless one is doing a Verniage type severing of columns and that is not in evidence nor supported by either side of this debate.

After collapse initiation the falling mass will primarily impinge upon the floor pans, in both towers. Having failed that floor pan the material then continues and unless it had come to a complete stop before failing the first floor pan it will now hit the next floor pan at greater velocity (simple high school physics that any science researcher would understand, even biologists) AND include the mass of the first failed floor minus any debris that exited to the side. To slow the collapse enough material would have to exit to the sides to offset the greater dynamic force cuased by increased velocity and increase in falling mass.
The vast majority of debris that fell outside the footprint of the towers consisted of lightweight/less dense material and material that began near, or at, the perimeter indicating that a great deal of that mass did remain inside to collapse floor pans.

BTW IIRC femr's calculations show that the acelleration was not uniform and constant but that it did vary.
Indeed even with a controlled demolition there is no way to have absolute uniform and constant acelleration unless one blows columns at all levels at the same time. Obviously that did not happen.
Click to expand...

jaydeehess said:
Because they confuse reduced acelleration with decelleration(negative acelleration)

Which brings up the question; "What is the smallest detectable change in acelleration possible in viewing a video?"

If the change in acelleration lasted less than 0.033 of a second then it may well be undectectable since it would only be in effect over the course of one frame of video.
Thus if the first floor pan failed in 33 milliseconds it is nigh on undectable.
A floor pan concrete was 4 inches thick plus the steel pan it was poured over and the trusses were a meter or less from top to bottom chord. Let's call it 1 meter thick in total.
If the upper section was falling at 90% g and fell through 3 meters the mass fell through the floor pan in approx 5 frames.
So theorectically IF one were able to measure the acelleration of the top section mass one might be able to see a change in the acelleration.
But wait,,, we are idealizing many aspects here;
- the top section is considered infinately stiff in all dimensions
of course it isn't, it will flex and distort at least a small amount confusing any measurement of acelleration.
- the top section is considered to have hit the lower section simultaneously accross its floor pan.
it would not have obviously, further confusing any precise measurement of acelleration.

Why?
Because acelleration is not directly observed. One can only measure position and time. The velocity of an object is taken to be the change in position between time intervals AND acelleration is the difference in velocity between subsequent intervals.
If you measure position every video frame you can get that position every 0.033 seconds. There will be an inherent error in the position measurement (+/- 0.x meters)
In simplistic error calculations;
You can therefore calculate average velocity over that 0.033 seconds and average acelleration over 0.066 seconds.

In determining average velocity between frames p2-p1=d1 v1=d1/t1 the margin of error of d is twice that of either p1 or p2. Do the same for p3-p2=d2 v2=d2/t2
Now we take v2-v1=delta v a=delta v/t2

Now let's break down a probable sequence of events from the idealistic scenarios.

Of course p1 would be the initial state of the tower before collapse so at the first frame after collapse initiation you can get an initial acelleration. It will fall for approx 25 frames of video before the upper section floor pan impacts the lower section floor pan.
BUT depending on where the columns failed (at floor level, halfway between floors, near the ceiling) the upper section columns will impact floor pans before the upper section floor pan reaches the lower section floor pan. In other words the effect of collission on acelleration will be spread out over this entire 25 frames before the two floor pans meet. thus perhaps a 0.9 g acelleration over this part of initial collapse.

The columns sections will easily punch through the floor pans further weakening them by fracture of concrete and steel before the upper section floor pan hits. This may or may not immediatly fail the lower section flor pan but probably will immediatly fail the upper section floor pan by lifting it off its seats.
Change in the roof line acelleration is minimal as the only energy used so far is to lift one floor off its seats and to punch holes in one floor pan.
Upper section continues down at essentially the same acelleration as before. column sections now reach the second lower section floor pan and punch holes in it while the second upper section floor pan reaches the other two. Given the degree of damage done to both of these floor pans, their trusses and truss seats, if the first lower section trusses and/or seats have not all failed, they do now. Probable that some area of flooring failed on first contact while others failed on second pan contact especially for the south tower.
Roofline acelleration, perimeter column acelleration of the top section is barely affected as failure is spread over several floors.

After a few levels all of the upper section has been converted to rubble but all this rubble, including some hefty steel core column parts, is moving very quickly now and thus exerting greater dynamic force on subsequent floor pans.

perimeter columns fail ahead of core columns but lag behind floor pan failures.


At least that's how I envision it.
Some people will however demand that tons of high explosives or thermite or unknown weaponry would have to be used.
Click to expand...

In terms of NIST and the molten metal, I did anything but debunk myself. It's been proven many times as you've seen it appears silvery at those temperatures.

It's also been proven that normal office supplies simply will not mix with molten aluminum. See below experiments. In the first video Jones analyzes a piece of the metal and shows it is not aluminum. So if that were aluminum I would expect it to be silvery, if building supplies were mixed in they would be on fire and apart from the silvery liquid.

In regards to your theory on the collapse. You will need to give me a few days to reply to you mathematically. I want to make sure I have read and understood it all and can reply adequately. I will post when I am ready.


http://www.youtube.com/watch?v=ezIU6ZxYU3A&NR=1

http://911review.com/articles/jones/experiments_NIST_orange_glow_hypothesis.html

http://www.journalof911studies.com/...rldTradeCenterBuildingsCompletelyCollapse.pdf

http://www.youtube.com/watch?v=5d5iIoCiI8g
 
Most of the thread was about molten metal in which most people said they don't know if it's aluminum or not. Certainly reasonable doubt to what it is.
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I see. You're claiming victory based on the fact that there MIGHT have been molten steel.

Golly gosh gee whiz, with arguments like that I'm not sure why a New InvestigationTM hasn't happened already.

"Dear Congress,

I have imagined evidence that, if it existed, would point to 9/11 being an inside job. I don't actually have this evidence, and it might not actually exist. But I'm just saying if it did. I think you should stop everything you're doing and launch an investigation into whether Bush had anything to do with the 9/11 attacks. The evidence I am imagining in my head suggests he was behind it all."
 
1337m4n said:
I see. You're claiming victory based on the fact that there MIGHT have been molten steel.

Golly gosh gee whiz, with arguments like that I'm not sure why a New InvestigationTM hasn't happened already.

"Dear Congress,

I have imagined evidence that, if it existed, would point to 9/11 being an inside job. I don't actually have this evidence, and it might not actually exist. But I'm just saying if it did. I think you should stop everything you're doing and launch an investigation into whether Bush had anything to do with the 9/11 attacks. The evidence I am imagining in my head suggests he was behind it all."
Click to expand...

Well let's look at it in reverse. I think we can all agree that if there is molten steel there is a huge problem right? It might NOT be molten aluminum. There is reasonable doubt to what it is. Do you realize we've (if you're American) been fighting for 10 years that no reasonable conclusion can be based on? I would say in my opinion based on everything I've seen and read I am around 95% sure it is steel. I know others don't feel that way. But are they 95% sure it's aluminum? I think most looking at the evidence would say not. I know there is more to it, but there is also more discrepancies, all you have to do is look at my OP. As I've said the evidence points greatly in favor of it being molten steel. It's not silvery (as lead and aluminum are) and when mixed with normal office supplies, the supplies will just fall off leaving the color aluminum. As shown in the experiments. I want to paste this video again for you, Jones obtained a piece of the material and determined it is not Silver. What procedure he used, you will have to take it up with him, but it is what he concluded.
http://www.youtube.com/watch?v=ezIU6ZxYU3A&NR=1

Edit: My personal opinion is Bush had little to nothing to nothing to do with 9/11.
 
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Why is it that the only sources ever used are youtube, or 911<insert "scholarly" sounding name here> to show allegedly "credible" evidence of this thermite controlled demo?
 
Grizzly Bear said:
Why is it that the only sources ever used are youtube, or 911<insert "scholarly" sounding name here> to show allegedly "credible" evidence of this thermite controlled demo?
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This is an argument based in appeal to authority.
 
tmd2_1 said:
This is an argument based in appeal to authority.
Click to expand...
Actually, it's merely questioning your lack of credible authority. In addition to your previously discussed lack of logic, evidence, and reason.
 
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