Fyziks 101

[DavidJames]

Care to dispute this explanation TF?If he does, I bet it will include a detailed technical description which would include one or more of the following engineering acronyms.

LOL, LMAO, LMFAO, ROTFLMAO

[R.Mackey]

Well, this thread has become just another rerun of the Truth Movement's Greatest Misses, and Turbofan's outbursts are borderline at best, so I won't be responding to him any further.

I just want to clean up one last, eye-opening pack of misinformation regarding basic physics, in case anyone should happen to read this and get confused. If, gentle reader, in the future you find yourself being swayed by this guy's arguments, keep in mind that his grasp of physics is almost completely wrong. The only person more ignorant would be Killtown, and that, maybe. So get a second opinion. Ask me, ask other posters here. If you don't trust us, talk to a physics professor. These mistakes are so fundamental, it won't take long to clear them up, and you may learn something in the process.

R. Mackey:

Yes, static pressure within the tower is equal to the outside pressure.

Yes, dynamic pressure is added to static pressure to arrive at total pressure.

However, the dynamic pressure you are describing only has to overcome
ambient pressure to escape the building. I'm sure you will agree, there
was no form of significant pressure wave entering the building due to a
wind storm?

Therefore, the falling floor in your example would not be able to build
enough pressure against the window with a large opening at the opposite
side


The total pressure is the sum of static and dynamic pressure. Dynamic pressure is calculated as ρ v2/ 2. See Bernoullli's Theorem (http://en.wikipedia.org/wiki/Bernoulli_theorem) for the complete explanation. This governs a lot of fluid motion behavior at reasonable speeds.

The static pressure inside the building and outside the building is the same before the collapse begins. Because there is no motion approaching the speed of sound -- at least early in the collapse -- there are no appreciable compressibility effects, and so the static pressure remains the same.

What changes, of course, is the dynamic pressure term. As the collapse gets underway, the air inside the structure is moving, pushed by falling floors. The air outside the structure doesn't move very much, since it has many more ways to get out of the way. This creates a rise in the dynamic pressure, but the static pressure stays the same.

As a result, the pressure inside exceeds the pressure outside. There is no "balance," and there is no "overcoming of the ambient pressure." The ambient pressure inside the structure is already enough to balance the ambient pressure outside. So any rise in the dynamic pressure means air leaves the structure. Just like you can use the Bernoulli equation to convert velocity to pressure, you can convert pressure back to velocity (for reasonable conditions).

This should not be counterintuitive. Of course the air will leave the structure. It's moving! It can't just stop moving unless there is something to oppose its dynamic pressure.

The argument Turbofan originally clung to was that the large holes in the structure would bleed away the pressure quickly. Well, no. If the pressure rise had been static, that would be true, because we would not have a sealed container or anything even close to it. In the case of dynamic pressure, however, the dynamic pressure only disappears when the fluid stops moving. This takes time. A larger hole means more air exits that side, and the greater air motion means more rapid dissipation, as the air's inertia is mixed with the outside air. But you still have the same dynamic pressure all over the place. Whatever the air's motion is, at any point, you can compute the dynamic pressure. And the air is moving even far away from the giant hole left by the aircraft.

If this was not the case, then things like ceiling fans wouldn't work at all. There's not just a "big hole" near a ceiling fan -- it's running practically in free space! So why doesn't the air just dodge the ceiling fan and stay at ambient pressure, moving basically nowhere? Or why does even merely waving your hand create a detectable breeze? Answer, because the air acquires inertia. That's what the dynamic pressure essentially is. The ceiling fan creates a substantial dynamic pressure on one side, and a negative dynamic pressure (though still positive total pressure) on the other side, and this means air motion, in this case air motion at a few meters per second. This doesn't just instantly dissipate. It can only do so through mixing, and so while a ceiling fan will not create a beam of moving air hundreds of meters long, it will create airflow several meters away. Even with no containment whatsoever. Even if operating in the open.

The situation in the Towers is vast by comparison. We have floor pans 4,000 square meters in size moving several meters per second, and with much better containment than a ceiling fan. Just because there's a hole on one side of the structure does not mean that there won't be air trying to escape in other places.

Besides Bernoulli, if we assume the air is incompressible (which is a reasonable simplification here), we can also solve for the fluid velocity through simple conservation of mass. We know how much mass is being pushed down by the upper block. This is the exact same mass that has to leave through whatever holes are available. Since the holes total a smaller area than the floor pans, the speed of the fluid is higher through the holes than it is at the face of the floor pans -- A1 v1 = A2 v2.

Energy, however, is not so easy to solve, because the floor pans are pushing the fluid, thus injecting energy into it. I had a lengthy discussion with Gregory Urich on this topic as it pertains to WTC 7, as seen in this thread (http://forums.randi.org/showthread.php?t=109833). In posts such as this (http://forums.randi.org/showthread.php?postid=3565678#post3565678) and this other one (http://forums.randi.org/showthread.php?postid=3599645#post3599645), I work with Gregory to even estimate the actual energy and heating experienced during the WTC 7 collapse. It's more than you might expect.

Turbofan, in essence, has provided us with the fluid equivalent of the "Net Force = 0" mistake made by other, equally ignorant Truth Movement bravos in the past. His insistence that the total pressure outside is equal to the total pressure inside is nonsense. Because the static pressures are the same, this is only true when the dynamic pressures are zero, i.e. velocity equals zero.

What we see from the video, instead, is a fairly high but still well subsonic fluid velocity. This velocity compares very nicely to what we compute with these methods, i.e. the "puffs" and "squibs" and so on are a perfect fit to simple air expellation as the collapse begins. It is in no way consistent with the supersonic bursts associated with explosives. Anyone with the faintest understanding of this subject would be daft to conclude otherwise.

This is why a grounding in elementary physics is useful. To my knowledge, there is not a single MIHOP hypothesis that cannot be discarded using basic physics alone. This is also why the Truth Movement has found it impossible to produce anything in support of itself that survives legitimate peer-review.

[LashL]

Read up on D. Griffin and K. Ryan!



Quite aside from R.Mackey's excellent and more than sufficient smackdown above, Turbofan's lame appeal to the false, entirely unfounded, and entirely unsupported "authority" of the likes of David Griffin and Kevin Ryan just cracked me up, so I couldn't resist adding this:

:dl: :dl: :dl:

[rwguinn]

mumble mumble
goalposts.. goalposts ..mumble know they were here...
Are we in the stadium yet?

are we playing Football, soccer, Australian football, or baseball? Just whereinhell are we headed, here?

[Disbelief]

"nearer 15 seconds"

Wow, I'll give you that extra 5 seconds! You don't see anything wrong
with that?

Ten seconds was taken from several video sources. YouTube is not
blocked here (you can still link videos).

So, 50% greater time and you don't see anything wrong with saying "near freefall?" So if someone wanted to pay you $150,000, would you say you would take $100,000 because it is near enough?

[Turbofan]

As a result, the pressure inside exceeds the pressure outside. There is no "balance," and there is no "overcoming of the ambient pressure." The ambient pressure inside the structure is already enough to balance the ambient pressure outside. So any rise in the dynamic pressure means air leaves the structure.

You are saying the exact same thing I said with a bunch of smoke and mirrors
around it!

If the static pressure is equal inside and outside the building, then the
rise in dynamic pressure causes the flow to move from inside the building
to outside the building (overcoming only ambient pressure).

Or in other words; there was no appreciable dynamic pressure outside of the
large airplane hole to prevent the dynamic pressure build to escape unimpeded.

This should not be counterintuitive. Of course the air will leave the structure. It's moving! It can't just stop moving unless there is something to oppose its dynamic pressure.

Ding, ding! :cool:

The argument Turbofan originally clung to was that the large holes in the structure would bleed away the pressure quickly. Well, no. If the pressure rise had been static, that would be true, because we would not have a sealed container or anything even close to it.

How fast did we calculate the building to be moving within the first second?

No more than 9.8 m/s correct? (Notice everyone, that's speed, not acceleration :rolleyes:)

In the case of dynamic pressure, however, the dynamic pressure only disappears when the fluid stops moving.

Ding, ding! Like I mentioned before: Without pressure differential, you cannot
have flow.


This takes time. A larger hole means more air exits that side, and the greater air motion means more rapid dissipation, as the air's inertia is mixed with the outside air. But you still have the same dynamic pressure all over the place.

Whatever the air's motion is, at any point, you can compute the dynamic pressure. And the air is moving even far away from the giant hole left by the aircraft.

So then, please explain to me (and the others), how you get a jet of debris
from one side of the floor, if the giant hole exists on the other side which
would experience the same dynamic pressure? :confused:

[phunk]

So then, please explain to me (and the others), how you get a jet of debris
from one side of the floor, if the giant hole exists on the other side which
would experience the same dynamic pressure? :confused:

It's simple. The dynamic pressure doesn't look for the biggest opening and only go that way. It goes out through ALL of the openings. That includes flowing down through the core to lower levels.

[Turbofan]

It's simple. The dynamic pressure doesn't look for the biggest opening and only go that way. It goes out through ALL of the openings. That includes flowing down through the core to lower levels.

Oh, I see. Soooo...it has all of that volume to displace itself, yet it just
wants to jet out one way? :rolleyes:

[nicepants]

So then, please explain to me (and the others), how you get a jet of debris
from one side of the floor, if the giant hole exists on the other side which
would experience the same dynamic pressure? :confused:

It goes back to that whole "path of least resistance" thing that you truthers never seem to understand.

ETA: Oh, I see. Soooo...it has all of that volume to displace itself, yet it just
wants to jet out one way? :rolleyes:

It's not that it "just wants to jet out one way"...it's trying to equalize wherever it can. What part of "It goes out through ALL of the openings." was unclear to you?

[rwguinn]

It's simple. The dynamic pressure doesn't look for the biggest opening and only go that way. It goes out through ALL of the openings. That includes flowing down through the core to lower levels.

You mean that the far-off person you're yelling to has a greater chance of hearing you yell if you're facing his direction instead of away from him?
Imagine that!

[Myriad]

Oh, I see. Soooo...it has all of that volume to displace itself, yet it just
wants to jet out one way? :rolleyes:


How on earth did you get "just wants to jet out one way" from reading "goes out through ALL the openings"?

Perhaps you learned this technique of deliberate incomprehension from George W. Bush, who has often used it to distort opponents' viewpoints and interviewers' critical questions to his advantage.

If it's any less disgusting when you do it than when your role model Dubya does, it's only because your views are far less consequential.

Respectfully,
Myriad

[Turbofan]

It goes back to that whole "path of least resistance" thing that you truthers never seem to understand.

:eye-poppi

You mean, a hole the size of an airplane has more resistance than a window?


[QUOTE]It's not that it "just wants to jet out one way"...it's trying to equalize wherever it can. What part of "It goes out through ALL of the openings." was unclear to you?

Are you sure you know what you're talking about?

You are telling me that the air is going to build pressure against the window
and 'jet' out before it equalizes the volume adjacent? :eek:

I wont bet on it, but I'd think even Mr. Mackey will have trouble with your
post.

[Turbofan]

How on earth did you get "just wants to jet out one way" from reading "goes out through ALL the openings"?

Perhaps you learned this technique of deliberate incomprehension from George W. Bush, who has often used it to distort opponents' viewpoints and interviewers' critical questions to his advantage.

If it's any less disgusting when you do it than when your role model Dubya does, it's only because your views are far less consequential.

Respectfully,
Myriad

Explain how to produce a jet of debris out the side of the building, when
you have an airplane sized hole on the same floor.

Use this diagram to explain your answer:

http://www.procision-auto.com/Tino/911_pressure.jpg

Just to clarify, you are saying the pressure will build only on the right side
of the floor, and blow out the window...before it exits the large opening
on the left? :boggled:

[phunk]

No, the pressure will be everywhere, what part of that is so hard to understand. It will go out BOTH the big opening and the small one on the other side. Guess which one it will be moving through faster.

[Turbofan]

No, the pressure will be everywhere, what part of that is so hard to understand. It will go out BOTH the big opening and the small one on the other side. Guess which one it will be moving through faster.


That is not the path of least resistance!

Where is the big airplane sized jet of debris then? :rolleyes:

I love the guess work going on with you guys. Keep adding to your theory
until something makes a bit of sense.

[funk de fino]

That is not the path of least resistance!

Where is the big airplane sized jet of debris then? :rolleyes:

I love the guess work going on with you guys. Keep adding to your theory
until something makes a bit of sense.


seen as you continue to avoid post # 500

Were all the floors in the building open plan TF? If not what would this have done to the air pressure inside the building on various floors?

If you have a room on that floor that is shut off from the rest of the floor then the pressure in that room has no way of reaching the open hole on the other side of the building so it will follow the path of least resistance and blow out the window of that room. Correct?

[Turbofan]

RE:#500

It doesn't account for the core columns. It doesn't account for the mass
that is blowing apart before the support structure descends. I've already
posted this pages ago!


seen as you continue to avoid post # 500

Were all the floors in the building open plan TF? If not what would this have done to the air pressure inside the building on various floors?

If you have a room on that floor that is shut off from the rest of the floor then the pressure in that room has no way of reaching the open hole on the other side of the building so it will follow the path of least resistance and blow out the window of that room. Correct?

I guess the plane didn't knock down any of those "walls" huh? :rolleyes:

[funk de fino]

RE:#500

It doesn't account for the core columns. It doesn't account for the mass
that is blowing apart before the support structure descends. I've already
posted this pages ago!

It does not have to because the core remained standing after the floors gave way. I knew you would be unable to disprove it. After claiming the explanation did not even exist, you then fail to understand it.

The mass is not blowing apart. The floor above dropping on the floors below overloaded the design static loads for the floor therefore the floor connections failed. Once these failed the core and perimiter columns could no longer stand. It is all available to see and hear in videos. Unlike the demolition charges the truther bots claim blew the building apart.

Please explain why the floor connections would have held?

I guess the plane didn't knock down any of those "walls" huh? :rolleyes:

Speculation? Some truthers reckon the plane debris did not reach far enough to damage the cores so why would they have reached the other side of the building. Even if they could would the cores not stop debri from reaching them? Were the toilets and offices in the floors all open plan? If not then this explains differences in pressure and paths in the building for the air during collapse.

Please explain why this is not so?

[Turbofan]

It does not have to because the core remained standing after the floors gave way. I knew you would be unable to disprove it. After claiming the explanation did not even exist, you then fail to understand it.

Really? Then what force broke that core apart? I would obviously need
some sort large mass to squish it down vertically within seconds!


The mass is not blowing apart. The floor above dropping on the floors below overloaded the design static loads for the floor therefore the floor connections failed.

Right...300 ft of tower is missing before the support structure descends.

It's clearly shown in the video, and still frame photos linked in the first post.



Please explain why the floor connections would have held?

Because of the 47 core columns, and 230+ perimeter columns.

The pancake theory was debunked long ago my friend. Start catching up
to the new NIST excuse.


Speculation? Some truthers reckon the plane debris did not reach far enough to damage the cores so why would they have reached the other side of the building.
Please explain why this is not so?

Well, who are you going to believe? The truthers, or NIST? NIST says some
of the core columns were damaged. I guess we're at least mid point within
the tower huh?

No debris shooting out the plane hole though!

[WildCat]

Really? Then what force broke that core apart?

It's called gravity.

[Turbofan]

It's called gravity.

Well geez, we all better run outside soon because our houses are
going to fall from gravity! :rolleyes:

What a freakin' laugh this is...

[uk_dave]

Well geez, we all better run outside soon because our houses are
going to fall from gravity! :rolleyes:

I strongly suggest that if your house has suffered from structural damage then this is exactly what you should do.

What a freakin' laugh this is...
Here we go again.

[funk de fino]

Really? Then what force broke that core apart? I would obviously need
some sort large mass to squish it down vertically within seconds!

The core could not stand alone. After the lateral support from the connections between the permieter and th floor and the core was broken, then core collapsed.


Right...300 ft of tower is missing before the support structure descends.

It's clearly shown in the video, and still frame photos linked in the first post.

This is a lie. I have seen the videos they do not show what you say they do.

Because of the 47 core columns, and 230+ perimeter columns.

How was the floor connected to those core and permiter columns? This is what gave way first.

The pancake theory was debunked long ago my friend. Start catching up to the new NIST excuse.

This is not the pancake collapse initiation theory. This is the collapse progression theory as described by NIST in the December FAqs. care to disprove their calculations?

Well, who are you going to believe? The truthers, or NIST? NIST says some of the core columns were damaged. I guess we're at least mid point within the tower huh?

So all walls on the impact floor would have been knocked down? Even ones hidden by the core?

No debris shooting out the plane hole though!

And?

If you were half as smart as you think you are you would see you should have run back to the FDR thread. You are unable to understand the most basic of concepts and run away and refuse to answer simple questions when you realise you are wrong.

[WildCat]

Well geez, we all better run outside soon because our houses are
going to fall from gravity! :rolleyes:
Your house is is disconnected steel columns 60 stories high?

What a freakin' laugh this is...
Trust me, we're not laughing with you.

[Jonnyclueless]

I think Turbofan should start by reading the NIST report before making all these absurdly untrue claims about the building design. Clearly he has absolutely no understanding of the structure, so why wouldn't he read the report so he could learn about it?

[~enigma~]

I think Turbofan should start by reading the NIST report before making all these absurdly untrue claims about the building design. Clearly he has absolutely no understanding of the structure, so why wouldn't he read the report so he could learn about it?
Truthers read? Are you losing touch with reality?

[applecorped]

526 posts later and.......................nothing.

[beachnut]

...
How fast did we calculate the building to be moving within the first second?

No more than 9.8 m/s correct? (Notice everyone, that's speed, not acceleration )

No, after the first second the building is not moving at 9.81 m/s. Assuming a simple model.

At .87 second the building impacts the first floor below at 8.52 m/s, and instantly the new velocity is 7.86 m/s to strike the next floor at 1.27 seconds at 11.6 m/s. But no, the speed of the collapsing building is not 9/81 m/s after 1 second.

I thought you left to go to physics class?

[Turbofan]

No, after the first second the building is not moving at 9.81 m/s. Assuming a simple model.

At .87 second the building impacts the first floor below at 8.52 m/s, and instantly the new velocity is 7.86 m/s to strike the next floor at 1.27 seconds at 11.6 m/s. But no, the speed of the collapsing building is not 9/81 m/s after 1 second.

I thought you left to go to physics class?

I think you should take a class or two:

You just stated that the upper section hitting the floor(s) below ACCELERATED?

Once again, the floors have nothing to do with this!!! It's not a pancake
collapse! Columns are connected inside and out! You should learn how
the tower is actually constructed.

The floors could pancake down all day long, but you still have the core
to deal with.

You can't even give a reasonable explanation for the core columns throughout
your guessing.

[WildCat]

Turbofan is reduced to sputtering incoherent nonsense now I see.

[Grizzly Bear]

You can't even give a reasonable explanation for the core columns throughout
your guessing.

I gave you something to look at, you ignored it. How do we make you understand something you outright reject despite being a coherent subject? :rolleyes:

We gave you the explanation, but being the 'fyziks' genius you are you outright rejected what is a very simple concept in architecture and engineering.

[applecorped]

Turbofan is reduced to sputtering incoherent nonsense now I see.

When was he not?

[Grizzly Bear]

I think you should take a class or two:

You just stated that the upper section hitting the floor(s) below ACCELERATED?

Yes... the impact with the floor below reduces the acceleration some but when the floor gives way due to the dynamic load, ot, plus the other floors above fall another floor height. The net acceleration gain is greater than what is lost impacting the floors...

Once again, the floors have nothing to do with this!!! It's not a pancake collapse!

You are stuck in that world of collapse initiation. The initiating event was due to column failure in the impact zone.

But the progression was a pancake collapse. You can reject that all day but it happened during the progression whether you claim it did or not

Columns are connected inside and out! You should learn how the tower is actually constructed.
Right back atchya'... What I find hilarious is that you claim it didn't pancake yet right in front of you, we've shown the remnant core columns standing (even if only briefly) after the main collapse (supporting a pancake progression) and then you complain that the core shouldn't have collapsed (despite most rational people knowing that they were not design for horizontal forces)...

I thinks you are utterly confused about what you're arguing here... Try getting you claims straight... You can't seem to decide which to use to support you claims

[dudalb]

Turbofan is reduced to sputtering incoherent nonsense now I see.


And the Pope is Still Catholic........

[Arus808]

and he's been on my ignore list since page 2. really, anyone could see his nonsense from page 1. I gave him a chance to redeem himself, but like all troofers who come here, nothing but hot air.

[fitzgibbon]

I think you should take a class or two:

You just stated that the upper section hitting the floor(s) below ACCELERATED?

Once again, the floors have nothing to do with this!!! It's not a pancake
collapse! Columns are connected inside and out! You should learn how
the tower is actually constructed.

Yo! Physics genius! Even half in-the-bag and with only a high school understanding of Newtonian physics, it's self-evident that the floors accelerated. Wanna know why? 'Cuz they started from a static (not in motion) state! Ergo, any motion on their part over a given span of time represents acceleration from the previous span of time. What you seem to have been ducking-and-weaving is the amount of acceleration and the size of the forces involved. Whether this has to do with avoidance on your part or lack of understanding is out of my purview.

[fitzgibbon]

nothing but hot air.

Explains global warming post 9-11. ;)

[Corsair 115]

Well geez, we all better run outside soon because our houses are going to fall from gravity! Well, if you were to weaken or remove the key structural components of your house, it most certainly would fall from gravity.

I would have thought that point rather obvious.

[HawksFan]

I know I'm going to regret asking this, but TurboFan...if the floors pancaked "all day long" as you state they could have, what would then be connecting the core and outer columns that you claim were still connected?

[Newtons Bit]

Well, if you were to weaken or remove the key structural components of your house, it most certainly would fall from gravity.

I would have thought that point rather obvious.

I don't think most Truthers have figured out that there's an actual reason why we need to have columns etc in buildings or that bad things can happen when these are damaged/destroyed.

[tsig]

mumble mumble
goalposts.. goalposts ..mumble know they were here...
Are we in the stadium yet?

are we playing Football, soccer, Australian football, or baseball? Just whereinhell are we headed, here?


We are playing Calvinball.

[rwguinn]

We are playing Calvinball.

HA! You forgot the Yogi Berra mangling of a Tommy Lasorda statement.
Face down and look at the sky!

[GlennB]

You can't even give a reasonable explanation for the core columns throughout your guessing.

Large amounts of both lower core areas remained standing after the primary collapse zones (mostly floors and outer columns, but including a good deal of upper core structure) hit the ground.

Both 'remaining' cores - deprived of all of their external lateral support, some of their internal support, and impacted and damaged lower down by massive amounts of falling debris - then eventually collapsed. As they were bound to do sooner or later.

Hope that helps.

[nicepants]

[quote=nicepants;3906656]It goes back to that whole "path of least resistance" thing that you truthers never seem to understand.

:eye-poppi

You mean, a hole the size of an airplane has more resistance than a window?

No. But the window provides less resistance than the solid wall surrounding it.

You are telling me that the air is going to build pressure against the window
and 'jet' out before it equalizes the volume adjacent? :eek:

It depends on how much and how fast the pressure increases, the amount of pressure that the window can withstand, and the resistance encountered by said air in traveling towards the other opening.

That is not the path of least resistance!

Of course it is...there is more resistance to the air traveling 208 feet across the building to the larger hole than there is going through the open window.

[Newtons Bit]

Of course it is...there is more resistance to the air traveling 208 feet across the building to the larger hole than there is going through the open window.

Air behaves according to the principles of fluid mechanics. It is not an electrical current. It does not follow the path of least resistance. It has mass, and thus inertia and thus behaves according to laws of motion (i.e. will keep travelling in the same direction unless a force acts on it. Force = Mass *Acceleration) etc etc with some additional interesting effects not seen in solid body mechanics such a vortex shedding, turbulent flow rates depending on Reynolds Numbers, etc etc.

Please don't fall for Truther "path of least resistance" idiocy.

[nicepants]

Air behaves according to the principles of fluid mechanics. It is not an electrical current. It does not follow the path of least resistance. It has mass, and thus inertia and thus behaves according to laws of motion (i.e. will keep travelling in the same direction unless a force acts on it. Force = Mass *Acceleration) etc etc with some additional interesting effects not seen in solid body mechanics such a vortex shedding, turbulent flow rates depending on Reynolds Numbers, etc etc.

Please don't fall for Truther "path of least resistance" idiocy.

Thanks, well said. I was going to try to describe an analogy involving water but decided I didn't want to deal with the inevitable "water is not a gas!" response from TF.

ETA: Putting 2 unequal holes in either side gallon of milk will result in milk spilling out both sides, not just the side with the larger hole.

[X]

Really? Then what force broke that core apart? It would obviously need
some sort large mass to squish it down vertically within seconds.


Well there's your problem!

Who said anything about the core section being "squished down vertically"?
No wonder you're so confused.

Poor little truther.



The force is gravity.
You want to test how it can collapse a vertical structure?
Get some lego. Build a column as high as you can using the 4-peg square bricks.
Watch what happens when it fails.

[Matthew Best]

Well, who are you going to believe? The truthers, or NIST?

Yes, that is a difficult choice.

[beachnut]

I think you should take a class or two:

You just stated that the upper section hitting the floor(s) below ACCELERATED?

Once again, the floors have nothing to do with this!!! It's not a pancake
collapse! Columns are connected inside and out! You should learn how
the tower is actually constructed.

The floors could pancake down all day long, but you still have the core
to deal with.

You can't even give a reasonable explanation for the core columns throughout
your guessing.
Part of the core is standing, and all the floors are in a pile! Did you miss something? I made a simple model based on weight and my model matches the actual time most the mass hit the ground, 12.08 seconds. Do you believe in thermite, explosives and missed the fact two planes speeding did the damage to the towers and they fell?
Part of core still standing. just core.
http://i286.photobucket.com/albums/ll116/tjkb/wtccornerspireclose.gif
I cheated, I am an engineer, the collapse as seen makes sense to me, and I confirmed my work with others independent of NIST, the 9/11 commission, Dan Rather, and I also researched relentlessly to understand the man who designed the STRUCTURE. He said this is how the building would come down in fire failure with 7 to 11 times the impact damage he had designed the building for.

Alas, do you read, do you do research,? Or are you filled with false ideas based on who knows what, and fail to make rational conclusion on 9/11? Why do you believe in the truth movement, failed ideas a bunch of liars selling DVDs to idiots?

The floor may not pancake, but they hit each other at the about the time I gave you based on physics, using a simple momentum model and confirmed by video and the time of the collapse reaching the ground.

If you paid attention you know the cores took 20 to 30 seconds to completely collapse, so your core can stay, it is the floor being destroyed by the weight above that leaves the core bare, and the mass also destroys parts of the core as it goes. The core can not stand without the floors attached to the shell. A floor can only hold 25,000,000 pounds and they fail, as soon as the mass on one floor as the top fell, reached 25,000,000 pounds that floor failed and hit the next floor with more than 25,000,000 pounds and the race ends 12.08 seconds at the ground, the remaining core collapses due to lack of support. Of course we have massive steel shell coming off in 3 floor sections and core columns doing the same adding to the mass on the floors and destroying each other in a the race to release the 100 TONS of TNT energy just due to GRAVITY! GRAVITY is the biggest energy source in all CDs too. After you have over 11 floors failing, GRAVITY drives the rest of the destruction!

With lack of knowledge comes gullibility, you have been fooled, you lack experience in many fields that could be useful for avoiding the ignorance of the truth movement lies. Try physics, engineering, and flying.

Do you know what one floor structure weighs with all the junk on it? Do you know what an average floor cross-section weighs on average, with core and shell included?

These are the thing you need to do a momentum model. It is amazing how a simple model based on weight and momentum at each floor, matches the time of the falling towers.

BTW, what was your theory on the towers falling?

The actual reason the towers fell are aircraft impacts 7 to 11 times greater than design was for, impact knocked off fire protection on steel and destroyed the fires suppression systems, 66,000 ponds of jet fuel ignited fires on many floors at the same time, large office fires continued till the building fell, and the steel was subject to high temperature weakening it. Then the tower collapsed. It takes about 11 floors, plus a pound, to overcome the structure below and have what we see on 9/11.

Were you the one using car and bus analogies for the WTC? That was funny.

[Corsair 115]

Air behaves according to the principles of fluid mechanics. It is not an electrical current. It does not follow the path of least resistance. It has mass, and thus inertia and thus behaves according to laws of motion (i.e. will keep travelling in the same direction unless a force acts on it. Force = Mass *Acceleration) etc etc with some additional interesting effects not seen in solid body mechanics such a vortex shedding, turbulent flow rates depending on Reynolds Numbers, etc etc.Speaking of air, there was an interesting piece on the show Daily Planet which runs on Discovery Channel Canada.

It was about this facility in Australia where they are doing research work on scramjet engines. To recreate the ultrasonic airspeeds needed to test different engine intake designs, they were using air under high pressure in a steel tube, an air cannon of sorts. A massive piston rapidly compressed and heated the air until it punched through a steel plate, thus yielding a (very short duration) blast of air at the necessary speed and temperature that flowed past a stationary model of the intake.

To be specific, a steel plate two millimetres thick had a sizeable hole punched through it by nothing more than air.

[Mancman]

Right...300 ft of tower is missing before the support structure descends.

It's clearly shown in the video, and still frame photos linked in the first post.




You are a liar. Or completely insane.

http://i33.tinypic.com/143ly8o.jpg

Look at the drivel that constitutes your argument and entire movement. The 'support structure' is quite obviously being torn to pieces by the GPE of the top section. Why would you try and lie about a directly observable event?

[pomeroo]

Well geez, we all better run outside soon because our houses are
going to fall from gravity! :rolleyes:

What a freakin' laugh this is...


Okay, we get the idea that you are a rock-headed ignoramus who is impervious to facts and reason. Now, how does making a horse's ass of yourself help to promote your evil cause?

[Minadin]

Thanks, well said. I was going to try to describe an analogy involving water but decided I didn't want to deal with the inevitable "water is not a gas!" response from TF.

ETA: Putting 2 unequal holes in either side gallon of milk will result in milk spilling out both sides, not just the side with the larger hole.

And, if the smaller hole is lower in the gallon jug than the big hole, it will squirt out faster, and for longer.

But, I have thought of a good water based 'analogy' we can describe.

Let's pretend that a 15,000 gallon (60,000 litre) water balloon smashed into the building you're in right now at 500 miles per hour. (800 kph) Maybe it was shot out of a giant cannon by reptilian jews from outer space or something. How well do you think that building would hold up? What would the damage be like? How would that be different if it was filled with kerosene instead of water?

[Bananaman]

No malice intended, but after all this nonsense I think it's evident that what Turbofan needs more than anything is psychotherapy, particular focusing on his ego problems (Napoleon complex or something similar, I'll leave it to the experts to determine) and his paranoia.

This would do him a hell of a lot more good in the short term than sticking him in a physics class where he can leer and drool at the back drawing weird pictures in his folder while squinting at the teacher thinking he knows more than she does.

Bananaman.

[jaydeehess]

Again with this DROPPED BS!

The upper section did NOT drop upon 'initiation' of collapse.

Everything was connected by core and perimeter columns!

Again with the complete misunderstandiing of the structre and what was happening or a wilfull ignorance.

While the columns were losing strength due to heating the buiklding twisted and sagged and the loads on those columns were redistributed to other, less affected columns. However as the fire spread and more columns were affected there came a time when the load being redistributed could no longer be held by the remiaining columns and they all buckled and bent under the load in very quick succession.

THEN, post initial collapse, the upper block was essentially falling upon the FLOORSPACE of the next level and thus rather than the mass of the upper block being distributed to the columns it was ripping the floor trusses away from the perimeter and core columns and,,,, you can review my previous posts,,,,,,,,,,,,

[Mr.D]

ego problems (Napoleon complex or something similar, I'll leave it to the experts to determine) and his paranoia.


Hmmm ... Attention seeking by the deliberate act of inflicting idiocy on others ...

Anyone want to propose Munchausens (http://en.wikipedia.org/wiki/Munchausen_syndrome) by idiocy for inclusion in the next DSM?

[tsig]

HA! You forgot the Yogi Berra mangling of a Tommy Lasorda statement.
Face down and look at the sky!
Kick dirt on the umpire score 15 points. Only in the fifth inning of a tie game.