The Obligatory 9/11 Thread Part II

[Kat Dorman]

That g is gravitational acceleration.

But the mass m can only accelerate through the distance h if that distance is EMPTY SPACE.

Incorrect.

The mass cannot accelerate through mass strong enough to support it.

Correct. But it can move through it while its velocity decreases, if it had sufficient initial momentum. If a support is compressed enough, it will fail. Then it can no longer support even the static load. Then it DOES accelerate.

You still think the supports afford the full capacity all the way through descent, despite showing you load-displacement curves for steel column numerous times which depict a peak capacity followed by rapid capacity decline after failure. Paper loops don't act like steel columns in that respect.

The critical aspect you (intentionally) overlook is FAILURE.

So the only energy is the kinetic energy of the falling top portion which has to lose kinetic energy to destroy the supports below so it slows down.

Losing some energy is not the same as losing all. You think becauses it loses some energy with each collision, it must eventually lose it all and come to a stop.

Yeah, if it were horizontal! Or upside down. Or if the supports are paper loops, apparently.

But since mass drops further with each failed level, it also loses PE incrementally, even in your model. If it dissipates more KE than PE lost at each level, it will arrest. If not, it won't. It's as simple as that. Yours arrests. Says nothing about the tower.

The washers must be pushed down from above and the paper loop supports must be crushed in the process causing the falling mass to lose velocity and kinetic energy.

Falling mass also loses PE. Empty space has nothing to do with it. Do a few pushups. Do you do work against gravity when pushing upward? Of course. When you go back down, gravity does work on you. Going up, your body gains PE, then loses it going down. Did your arms disappear? Of course not. Your body loses the same PE whether you lower yourself down slowly or someone chops your arms off and you drop.

The difference is the resistive force, which has nothing to do with PE gain or loss.

UNTIL IT STOPS leaving most of the structure intact.

In your model.

Make a physical model do what your mathematics says.

http://www.youtube.com/watch?v=prwvj-npt5s&feature=related
It's not a house of cards, and it most certainly isn't paper loops and washers. It's a ******* building.

Let me guess. It was more than 15% at the top (or is it 10% now?). It wasn't at least 33 stories (the 'special' number you chose for your model). Where will the goal posts go next? Are you going to disqualify it because I didn't build it? Or maybe because it wasn't made of paper loops and washers?

Haahaahaahaaahaahahahahaahahahaaahaahaahaahaahahaaahaaaa!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[Kat Dorman]

I decided to "View all comments" on the youtube link above and search for "psik" and, sure enough, he's already seen the video:

Well it looks like that video proves Bazant is wrong because the top falling portion is being destroyed as it destroys the portion below. But that does not look like a steel frame building.

The variation in distribution of strength & mass is greater in a skyscraper more than 1000 feet tall.

Try finding the total weight of a complete floor assembly, 205 foot squares. Those things that may or may not have pancaked. ll that talk and we don't know what they weigh after EIGHT YEARS. LOL

LOL, yeah. Now I know what your next goal post move is, having already seen a building collapse that unequivocally meets your challenge to a 'T".

QUOTE: "But that does not look like a steel frame building."

and

QUOTE: "The variation in distribution of strength & mass is greater in a skyscraper more than 1000 feet tall."

Well, to hell with your model then. Paper loops and washers DO NOT look like a steel frame building. Your model does NOT have the variation in distribution of strength & mass of a skyscraper more than 1000 feet tall. Your model is disqualified by your own stated criteria.

Therefore, EVERY time you ask for a physical model to prove my assertions, I will ask you for the same since you haven't made any.

[Kat Dorman]

So build a model that can collapse COMPLETELY.

No, you first. Build a model which:

- looks like a steel framed building
- has variation in distribution of strength & mass like a skyscraper more than 1000 feet tall.

which ARRESTS.


Waiting....

[psikeyhackr]

http://www.youtube.com/watch?v=prwvj-npt5s&feature=related
It's not a house of cards, and it most certainly isn't paper loops and washers. It's a ******* building.

Let me guess. It was more than 15% at the top (or is it 10% now?). It wasn't at least 33 stories (the 'special' number you chose for your model). Where will the goal posts go next? Are you going to disqualify it because I didn't build it? Or maybe because it wasn't made of paper loops and washers?

Haahaahaahaaahaahahahahaahahahaaahaahaahaahaahahaaahaaaa!!!!!!!!!!!!!!!!!!!!!!!!!!!!

OH WOW! That was so funny and impressive.

Like I haven't seen that before and before and before. It is posted by so many people thinking they are refuting something.

How many times have I said 15% or less falling on the rest?

They dropped 3 stories through a height of 2 stories. The building looked less than 16 stories tall. So if it was a 15 story building it was 20% falling on 75% allowed to drop through 13% of its height.

The north tower was 14 stories falling on 95 stories through 1 story of empty space SUPPOSEDLY. So 12.7% onto 86% with less than 1% of the height to fall.

But how is the mass distributed in a building over 1000 feet tall versus something less than 200.

I have never seen that technique used on a REAL SKYSCRAPER.

Oh yeah, you proved something. Was it a steel frame building. Yeah, I'm SOOO impressed.

I dropped 12% by height with my washers test.

I chose 33 because it can be factored by 11 like the WTC and would not be much more than 2 feet tall leaving me significant room to drop my mass on a 4 foot dowel. When I purchased the washers I had no idea how many washers it would take to crush a single paper loop. I was expecting it to be 4 or 5. It turned out to take 12 to 17. So the paper loops at the top are almost certainly stronger in proportion to the weight than the WTC. So dropping from a greater height makes sense.

But I notice in your video that they don't show how much of the building, if any, was left after the deliberate collapse. That video never shows the base at all so we can't even be sure of the number of stories.

You can go back to laughing now. Grade school kids should laugh at the United States over this crap for the next 1000 years.

psik

[Kat Dorman]

Like I haven't seen that before and before and before.

And it should've silenced you long ago.

It is posted by so many people thinking they are refuting something.

It does, quite strikingly.

How many times have I said 15% or less falling on the rest?

True, you have said that. You've also said:

- looks like a steel framed building
- has variation in distribution of strength & mass like a skyscraper more than 1000 feet tall.

which eliminates your model from consideration. You may as well have built a shed in you back yard, it would be more useful. I understand you reject a smaller portion of a REAL building completely crushing a larger lower part as a valid experiment. Fine. I'm telling you that I reject a dinky stupid paper loop and washer model on the same grounds, for obvious reasons. You satisified the less than 15% criteria, but so what? It's not enough, by your own stated criteria.

They dropped 3 stories through a height of 2 stories. The building looked less than 16 stories tall. So if it was a 15 story building it was 20% falling on 75% allowed to drop through 13% of its height.

So what? It was a BUILDING, not a stupid paper loop and washer extravaganza.

The north tower was 14 stories falling on 95 stories through 1 story of empty space SUPPOSEDLY. So 12.7% onto 86% with less than 1% of the height to fall.

The south tower was a greater percentage.

But how is the mass distributed in a building over 1000 feet tall versus something less than 200.

Or, more importantly, over a 1000 feet tall versus something less than 4 feet tall?

Haahaahaahaaahaahahahahaahahahaaahaahaahaahaahahaaahaaaa!!!!!!!!!!!!!!!!!!!!!!!!!!!!

What a joke your entire position is.

Oh yeah, you proved something. Was it a steel frame building. Yeah, I'm SOOO impressed.

I dropped 12% by height with my washers test.

Oh yeah, you proved something. Was it a steel frame building? Nooooo, it was ******** paper! Yeah, I'm SOOO impressed.

I chose 33...

No one gives a damn why. You could've read the tea leaves for all I care. I've heard the stupid explanation a half dozen times and got it the first time.


Still waiting for a physical model which ARRESTS.....

[Kat Dorman]

Found one for you. Here's a building which does ARREST:

http://www.youtube.com/watch?v=Z1vzg1lAIvM.

It's a building, not (haha) papers and washers. That ought to demonstrate something.

Damn. Disqualified because it's a crush up. Not <15% dropped through 1% on the lower 84%, it's roughly the top 80% dropped through 20%. It comes to an abrupt stop right away!

Shame a dropped building doesn't qualify, but somehow paper and washers on a dowel does. I'll keep looking.

(Not steel framed, either, nor built like a skyscraper over a 1000 feet tall. But then, neither are paper and washers on a dowel. Funny that.)

[uke2se]

Model for collapse: star with mass of around 1.4 solar masses.
Method of collapse: gravitational collapse during supernova event.
Result: much reduced in size.

I'm sorry I haven't made this model myself, but I don't see any reason why I can't use a model already at hand.

Well played.

Good, you can calculate the mass relative to the WTC then.

psik

What was the mass of your model relative to the WTC?

[uke2se]

Damn, I should read on before replying. That's some serious ownage of psik's "arguments", Kat. Well played!

[Kat Dorman]

That's some serious ownage of psik's "arguments", Kat. Well played!

Thank you. It was, however, a complete and utter waste of time. Guaranteed.

[Xaihe]

You can go back to laughing now. Grade school kids should laugh at the United States over this crap for the next 1000 years.

psik

Doubtful, and high school kids will be laughing at the idea that a free falling mass in a gravitational well has a constant speed (implication of your physics) for much longer than 1000 years:

The mass cannot accelerate through mass strong enough to support it. Like a book sitting on a desk the NET FORCE is ZERO. It can't fall. So the only energy is the kinetic energy of the falling top portion which has to lose kinetic energy to destroy the supports below so it slows down.

Perhaps a grade school kid doesn't see the problem in your reasoning right away, but I'm sure most highschool kids would. Your mistake is in the assumption that falling mass doesn't gain kinetic energy. Falling mass gains KE. If you disagree with this, then you're denying gravity. Simultaneously, falling mass loses KE when KE is transferred to another mass. However, KEgain - KEloss = KEnet can be 0 (constant speed) or greater than 0 (increasing speed) or smaller than 0 (decreasing speed). You seem to be fanatically set on the smaller than 0 scenario, no matter the case you're looking at. The fact that you find it funny tells me you would do well to find some professional to educate you in this matter.

Go ahead and tell me how wrong I am (without an explanation), because I have other ideas about why you fail to grasp this idea. Don't expect me to put forth all those ideas though.

[atrasicarius]

Remember the part about how there was energy equivalent to 94 tons of TNT released as the buildings collapsed in addition to the acceleration? Honestly, did you type that out just now, or just copy/paste it in from somewhere else? It's kind of hilarious after your last post about how energy doesnt matter.

A potential Energy calculation is mgh.

That g is gravitational acceleration.

But the mass m can only accelerate through the distance h if that distance is EMPTY SPACE.

The mass cannot accelerate through mass strong enough to support it. Like a book sitting on a desk the NET FORCE is ZERO. It can't fall. So the only energy is the kinetic energy of the falling top portion which has to lose kinetic energy to destroy the supports below so it slows down.

Epic basic physics fail. Potential gravitational energy is the measure of how much energy something could have if it dropped. That's why it's called POTENTIAL energy. A mountain also has potential energy, even though it's probably not going anywhere. As you may or may not be aware, energy is always conserved. Therefore, if an object has a certain potential energy at the beginning and a different potential energy at the end, then ALL of that energy went somewhere. If only some of that energy went into acceleration, then the rest went somewhere else. This is highschool level stuff, man. No matter what you think destroyed the towers, energy equivalent to about 94 tons of TNT WAS released during the collapse. That is a simple fact.

[psikeyhackr]

Epic basic physics fail. Potential gravitational energy is the measure of how much energy something could have if it dropped. That's why it's called POTENTIAL energy.

EXACTLY! So computing the potential energy of something that can't possibly fall is pseudo-intellectual bullshit.

Computing the potential energy of the WTC is for pseudo-intellectuals.

On my model the potential energy of the lower stationary portion is totally meaningless to what happens when I drop the falling portion so WHY DO THE CALCULATION?

It is more useless talk that may impress people that don't understand how useless it is.

The energy required to crush a paper loop is relevant, 0.118 Joules. I tested that by dropping various numbers of washers from specific heights to see what it took to just not quite crush a loop flat. Four washers dropped from 4 inches does the trick. The empty space between my mass to be dropped and the top of the stationary mass computed to be enough to flatten NINE paper loops. That is pretty much what happened.

That is the advantage of a controlled experiment over various videos of building demolitions. We can't even tell exactly how many stories that building had. And where was the equivalent of 4 ton girders being hurled 600 feet into the Winter Garden. Oh, maybe that was skittering not hurled. econ41 needs to get the wording right.

psik

[atrasicarius]

Epic basic physics fail. Potential gravitational energy is the measure of how much energy something could have if it dropped. That's why it's called POTENTIAL energy.

EXACTLY! So computing the potential energy of something that can't possibly fall is pseudo-intellectual bullshit.

Computing the potential energy of the WTC is for pseudo-intellectuals.

On my model the potential energy of the lower stationary portion is totally meaningless to what happens when I drop the falling portion so WHY DO THE CALCULATION?

It is more useless talk that may impress people that don't understand how useless it is.

The energy required to crush a paper loop is relevant, 0.118 Joules. I tested that by dropping various numbers of washers from specific heights to see what it took to just not quite crush a loop flat. Four washers dropped from 4 inches does the trick. The empty space between my mass to be dropped and the top of the stationary mass computed to be enough to flatten NINE paper loops. That is pretty much what happened.

That is the advantage of a controlled experiment over various videos of building demolitions. We can't even tell exactly how many stories that building had. And where was the equivalent of 4 ton girders being hurled 600 feet into the Winter Garden. Oh, maybe that was skittering not hurled. econ41 needs to get the wording right.

psik

>something that cant possibly fall
Read that part again, a little more carefully this time.

[psikeyhackr]

>something that cant possibly fall
Read that part again, a little more carefully this time.

Yeah, we have a problem with semantics and physics.

The rhetoric, oratory and sophistry bullshit used in European culture for the debating behavior is built on the psychology of STUPIDITY. AND THEN THE STUPID DEBATERS THINK THEY ARE INTELLIGENT. Still arguing about Marx and Keynes 41 years after the Moon landing while saying nothing about the planned obsolescence of automobiles. Extremely intelligent.

Suppose you have a 3 pound book sitting in the middle of a desk. IT CAN'T FALL. Suppose someone drops a two ton mass from 10 feet onto the book and it crushes the desk. Would you describe that as the book FALLING?

If a 20 ton section of column was 500 feet up and inside the core of the WTC and welded above and below and on all sides with horizontal beams then it COULD NOT FALL. Now SUPPOSEDLY mass came from above and forced it down. But we aren't told how much ENERGY WAS REQUIRED TO BEND ALL OF THAT STEEL but we are supposed to BELIEVE that it could all fall down. So we have all of this semantic debating bullshit based on grossly incomplete data and some people want to imply they are intelligent while ignoring the data which accurate physics would require. We aren't even told the distributions of steel and concrete in the towers by Official Sources. The best source is supposed to be a programmer in Sweden, like that isn't INCREDIBLY STUPID all by itself.

Like comparing the demolition of a 20 story building to the WTC. The mass distribution in that building might be similar to the TOP 20 STORIES of the WTC, not the rest.

So the obvious next bit of pseudo-logic is to compare it to my 2+ foot collapse demonstration. But I had control of all of the material there. It was delberately made AS WEAK AS POSSIBLE. Anyone that doubts it can try it for themselves. I can't prove that with a vdeo. ARE REAL BUILDINGS DESIGNED TO BE AS WEAK AS POSSIBLE???

Physics is not rhetorical pseudo-logic crap.

psik

[GrahamH]

The mass cannot accelerate through mass strong enough to support it. Like a book sitting on a desk the NET FORCE is ZERO. It can't fall. So the only energy is the kinetic potential energy of the falling top portion which is converted to has to lose kinetic energy to destroy the supports below so it slows down may speed up or slow down depending on resistance.

Fixed it for you.

[Kat Dorman]

Suppose someone drops a two ton mass from 10 feet onto the book and it crushes the desk. Would you describe that as the book FALLING?

Doesn't matter what you call it. As you're so fond of saying, physics doesn't give a damn about words - especially yours. The book loses potential energy as it descends, no matter the reason. Consider yourself informed again.

Like comparing the demolition of a 20 story building to the WTC. The mass distribution in that building might be similar to the TOP 20 STORIES of the WTC, not the rest.

I guess you know where I'm going next. Yes, you do:

So the obvious next bit of pseudo-logic is to compare it to my 2+ foot collapse demonstration.

Ah, it's not pseudo-logic for you to say two buildings are incomparable, but it is pseudologic to say a skyscraper is not comparable to a paper loop and washer model barely knee-high to a grasshopper.

Haahaahaahaaahaahahahahaahahahaaahaahaahaahaahahaaahaaaa!!!!!!!!!!!!!!!!!!!!!!!!!!!!

But I had control of all of the material there.

OK, boss. Inspires confidence.

It was delberately made AS WEAK AS POSSIBLE.

Lie by omission. As weak as you could make it yet strong enough to stand with a factor of safety - given your choice of material and design.

ARE REAL BUILDINGS DESIGNED TO BE AS WEAK AS POSSIBLE???

Do you really think they make them as strong as possible? The actually DO make them as weak as possible, yet above a certain threshold of safety. Exactly what you attempted to do but failed due to lack of engineering skills. By the use of math and physics which you hate so much and don't understand, engineers can make steel skyscrapers strong enough to stand yet weak enough to collapse given the right initial conditions. By contrast, you can't even engineer a 2 foot model to collapse with an ovesize drop.

But, then again, you didn't want it to collapse, did you? Could there be some experimenter bias?

[Kat Dorman]

If I wanted to design a model that could collapse completely, I would choose supports which are stiff over a very small range and then fail to zero or near zero capacity. Like steel columns. Unlike paper loops. Pasta...



There would have to be a good reason to do it, though, because life is too short for such trivia otherwise.

[aspire1670]

Physics is not rhetorical pseudo-logic crap.

psik

Except when you try to use it.

[Xaihe]

So the obvious next bit of pseudo-logic is to compare it to my 2+ foot collapse demonstration. But I had control of all of the material there. It was delberately made AS WEAK AS POSSIBLE. Anyone that doubts it can try it for themselves. I can't prove that with a vdeo. ARE REAL BUILDINGS DESIGNED TO BE AS WEAK AS POSSIBLE???

Let me show you how incredibly ridiculous this "WEAK AS POSSIBLE" nonsense is.
I'm making a model of a tower, composed of a single molecule of C2H2 (ethyn, acetylene). I made it as WEAK AS POSSIBLE! However, if I drop (in a vacuum in a laboratory) a single Helium atom on it (15.3% of the weight of the acetylene molecule), it doesn't collapse. I could also drop an Argon atom on it (69% of the weight of the tower) and it still won't collapse. There is NO DAMAGE AT ALL! Can you see the silliness of this "WEAK AS POSSIBLE" nonsense yet?

[psikeyhackr]

If I wanted to design a model that could collapse completely, I would choose supports which are stiff over a very small range and then fail to zero or near zero capacity. Like steel columns. Unlike paper loops. Pasta...



There would have to be a good reason to do it, though, because life is too short for such trivia otherwise.

So let's see you do it. TALK IS CHEAP!

That is the trouble with talking about things and doing things. When you try to do something you often find there was some detail that wasn't as small as you thought it was. When I went to buy those washers I ASSUMED they were the same size. They are quite consistent in outer and inner diameters but their thickness varied more than I expected.

I ASSUMED that 4 or 5 washers would crush a single paper loop under STATIC LOAD but it turned out to take from 12 to 17. So I ended up not having nearly as much variation in strengths of loops between washers as I was expecting.

So you can come here and TALK about you can do this and you can do that and this will happen and that will happen and expect people to BELIEVE it. But I am not even going to try to come up with verbal bullshit to refute you because that is all you are spouting VERBAL BULLSHIT.

So build it and SHOW US!!!

psik