Sir, Newton's Third Law is simple, but you misapply it to arrive to incorrect conclusions. I invite you to model this situation in any simulator of Newtonian mechanics of your choice, and you will find that your conclusion - that the upper part of the tower must be crushed equally to the bottom part of the tower - is wrong. If you like, maybe I could make such a simulation for you.
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Question for Apollo20
- Thread starter Golden Bear
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Or, if you like, you can make a simple experiment at your home.
Take two crushable objects, for example two equal pieces of cake, and a heavier object, for example a wooden cube.
Place one piece of cake on the floor, then hold the wooden cube just above it (ideally it should touch the top of the piece of cake on the floor) and place another piece of cake on the top of the wooden cube.
Then, let go of the wooden cube.
What do you observe? You observe that the bottom piece of cake is crushed significantly more than the top piece of cake. How is this possible, if, according to your logic, any force exerted by the wooden cube on the bottom piece of cake should be matched by an equal and opposite force on the upper part, and should therefore crush the top piece of cake equally?
The explanation is simple and obvious: the bottom piece of cake does indeed, according to Newton's third law, exert equal and opposite force on the wooden cube as the wooden cube crushes it. But the next step in your reasoning is fallacious: this does not mean that the wooden cube exerts the same crushing force on the top piece of cake.
I would like to emphasize that this experiment is not intended as any, however remote, approximation of the WTC tower collapse. No. It is intended as a practical demonstration that inserted mass breaks the symmetry of gravity-driven crushing (this is important), and a practical demonstration that Newton's third law does not imply that the top object must suffer equal destruction as the bottom object.
You may ask: in what kind of situation is the symmetry not broken by inserting a massive object? And the answer is simple: if the situation is truly symmetric. For example, if you place one piece of cake against the wall, then put a massive object next to it, and another piece of cake, and push against the outermost piece of cake, you will find that both pieces of cake will be crushed equally. (The massive object must be able to move freely on the floor; a toy car will be better than a wooden box.)
Exercise for readers: explain what makes the difference between the latter situation (where there is equal crushing) and the former (where there is not).
Take two crushable objects, for example two equal pieces of cake, and a heavier object, for example a wooden cube.
Place one piece of cake on the floor, then hold the wooden cube just above it (ideally it should touch the top of the piece of cake on the floor) and place another piece of cake on the top of the wooden cube.
Then, let go of the wooden cube.
What do you observe? You observe that the bottom piece of cake is crushed significantly more than the top piece of cake. How is this possible, if, according to your logic, any force exerted by the wooden cube on the bottom piece of cake should be matched by an equal and opposite force on the upper part, and should therefore crush the top piece of cake equally?
The explanation is simple and obvious: the bottom piece of cake does indeed, according to Newton's third law, exert equal and opposite force on the wooden cube as the wooden cube crushes it. But the next step in your reasoning is fallacious: this does not mean that the wooden cube exerts the same crushing force on the top piece of cake.
I would like to emphasize that this experiment is not intended as any, however remote, approximation of the WTC tower collapse. No. It is intended as a practical demonstration that inserted mass breaks the symmetry of gravity-driven crushing (this is important), and a practical demonstration that Newton's third law does not imply that the top object must suffer equal destruction as the bottom object.
You may ask: in what kind of situation is the symmetry not broken by inserting a massive object? And the answer is simple: if the situation is truly symmetric. For example, if you place one piece of cake against the wall, then put a massive object next to it, and another piece of cake, and push against the outermost piece of cake, you will find that both pieces of cake will be crushed equally. (The massive object must be able to move freely on the floor; a toy car will be better than a wooden box.)
Exercise for readers: explain what makes the difference between the latter situation (where there is equal crushing) and the former (where there is not).
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Golden Bear
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You little cake/wooden block analogy is meaningless in this discussion. Your disclaimer statement doesn't get you off the hook either. We're talking about the World Trade Center Collapse in case you forgot. Whatever principle you are trying to illustrate is meaningless. "Inserted mass"? Where did this inserted mass come from in the WTC?
If you're stacking two pieces of cake on the ground and dropping something onto them, then you have to be dropping cake. I'm so sorry this is so hard for you all to accept. I know you guys like to drop harder, heavier objects onto softer, more easily destructible objects (rock onto house of cards is still my favorite) and twist it to support your theory, but I can't make it any clearer for you that such analogies are meaningless in this debate. They do make your job easier though because you can cling to something that sounds good but is completely irrelevant.
Here's the real experiment, stack 3 identical pieces of cake on top of one another on the ground, drop a single piece of cake that is identical to the 3 on the ground onto them, and see what happens. Drop it from high enough and film what happens with a high speed camera and I guarantee you that the piece of cake you drop, if it identical to the 3 on the ground, will suffer damage at the exact same rate as the pieces of cake that are being impacted. Why? Because of Newton's Third Law.
I've read through Bazant's paper thoroughly. Please point to me where he takes this equal and opposite upward force into account.
Golden Bear
Scholar
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Well, that is an absurd statement. What is the magnitude of the force exerted on the upper part of the tower from the crushed debris, then? And where does it come from? It's my understanding that Bazant assumes each floor fully compresses when it is crushed. It seems logical then that any force on the crushed debris would be transferred up through the debris and into the upper block of floors. Or does the debris layer just magically absorb it?
You misunderstand Newton's Third Law. It's all about two bodies, and it's all about your frame of reference.
If you take the Earth as one body, and the building with a person standing on it as another body, then the Earth is, in fact, exerting an equal and opposite force upwards on the person/building body that is equal to the gravitation force being exerted on the earth due to the weight of the building plus the person.
If you take the person as one body and the building connected to the earth as another body, the Newton's Third Law dictates that the building/earth body is exerting an equal and opposite force on the human that is equal to the gravitational force being exerted on the building/earth body due to the human's weight.
Newton's Third Law does not discuss three different bodies that are interacting at the same time, so it doesn't help much when you're trying to analyze the behavior of the earth, building and person as separate bodies at the same time.
Nice try, though. Maybe you should go back and take Physics 101. I still remember the discussions we had about how important the frame of reference is in the analysis. It's also important in the conservation of momentum analysis, by the way. Does any of this ring a bell?
A W Smith
Philosopher
Im thinking of the upper block as a projectile.
post and run...
Newtons Bit
Penultimate Amazing
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Tweeter, do you have anything productive to add, or are you spamming to get to 15 posts?
TAM
Tam, did you have anything productive to add, or are you spamming to get to 20,000 posts?
See what I did there?
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No Beachnut, I find you particularly offensive on this forum. I don't believe with the skills you pretend to advocate, that you could have possibly got there with the English vocabularly you continuously use. i.e BS, BS, etc. That is your argument and one that I am sorry to say when I see your posts I just ignore.
As I have already said, the force comes from the crushed debris not falling freely. If the crushed debris was falling freely, it would exert zero force on the upper part of the tower. If acceleration of the crushed debris as it crushes the bottom part of the tower is a, the force exerted by the crushed debris on the upper part of the building is F=(g-a)/m, where m is the mass of the upper part of the building and g is the gravitational acceleration.
Just as the force exerted by the ground on a building is not fully transferred up through the building into a person standing on the roof, force exerted on the crushed debris is not fully transferred into the upper block of floors. Force is change of momentum over time. The debris layer does not absorb the momentum magically; it "absorbs" it physically. As the mass of the crushed debris increases, same force applied to it over unit time results in the same amount of momentum change, but less velocity change. Velocity change over time is acceleration.
To put it simple, applying the same force to an object with greater mass will cause the object to accelerate less, exerting less force on objects attached to it. If you apply force F1 to a rigid object X1 with mass m1, and there is a rigid object X2 with mass m2 attached to X1, force exerted by object X1 on object X2 (and by object X2 on object X1, of course) will be F2=F1*m2/(m1+m2), i.e. less than F1.
Yes, this is true. I am surprised that this realization does not help you see that your conclusions are incorrect.
Please realize that the force between the building and the Earth, and between the person and the building is absolute and can be directly measured - the latter being much less than the former. This directly invalidates your assertions that force is "transferred" through bodies.
Which is why it also doesn't help when you're trying to analyze the behavior of the bottom part of the tower, the crushed debris, and the upper part of the tower. Which is why I said that you misapplied Newton's third law to arrive to incorrect conclusion - specifically, that the force between the crushed debris and the bottom part of the tower is the same as the force between the crushed debris and the upper part of the tower.
You just explained, in your own words, why you cannot use Newton's third law to arrive to that conclusion. Do you not see that it invalidates your argument about the forces having to be equal?
I fail to understand the purpose of this remark.
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I expect you are as smart as JDX and his group. When will you present some facts to back up your non specific posts? Why not post something with some facts and evidence to support some conclusion of 9/11 truth, some idea of 9/11 truth and make history. You would be the first!
I find idiots in 9/11 truth to be offensive by misleading others, I find ignorance to be offensive in those too lazy and stupid to figure out the lies of 9/11 truth.
There are many who are fooled by 9/11 truth who have actually used their brains to prove they have the potential to understand 9/11 and think rationally. When will you?
You believe the BS of 9/11 truth? Feel free to post something from 9/11 truth that is not BS. I do not understand why I have to get out my engineering books, or my flying manuals to beat back the hearsay junk science of 9/11 truth. Do you?
Why do you have to use anything other than talk to battle the hearsay lies of 9/11 truth? Got something you think is a smoking gun. What fantastic story do you have that is so fact backed it can earn a Pulitzer Prize and expose 9/11 for the plot is was in your mind?
You asked me this -
The answer is 60,000 pounds of fuel, 10,000 gallons. Too technical for you? Oh, that is correct, you like BS of 9/11 truth, the pure smoking gun bs, the bs of thermite, the no facts bs, the hearsay bs. You do not like people to call it bs, but then you can not prove it is anything but. Darn. Bet you have to go work on your PhD of woo. Happy New Year, better check those thermite calculations again. Jones is allowed to spread lies with thermite, did you check out his latest find on the chips of red? With your PhD you could help Jones get the Pulitzer Prize for breaking the 9/11 plots using thermite. I found the same type of chips in my fire place. Wow.
You could peer review woo at the journal of woo with Jones.
Tell you what Dr. O, you could present something with some facts to back up some 9/11 truth stuff. Another dissertation so to speak. Something to prove your ideas on 9/11. Cool.
Darn, you are wrong, I have the skills and anyone with any ability to research anything (like you claim with your lies about degrees and such) could see 77 and 93 are typical high speed impacts. But then you must no have the skills you say you do, where as my skills are not bs like most 9/11 truth drones. Have you researched this enough to understand I am right, or are you still short on knowledge to understand anything 9/11?
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Golden Bear
Scholar
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This is where you are wrong. The crushed debris and the upper part of the towers are, according to Bazant, traveling downwards and crushing the lower structure as a single body. Bazant theorizes that, every time a floor is crushed, the crushed debris adds its mass to the upper section of floors, which continues to crush the lower structure. I'm afraid you don't understand Bazant's theory. There aren't three bodies in his equation, there are two.
Bazant doesn't get it both ways (and neither do you). He can't include the mass of the upper section of floors to in the force equation that destroys the lower structure without considering the upper section of floors a part of the body that is crushing the lower structure, and thus be acted upon by Newton's Third Law. The crushed debris is assumed to be fully compacted, so the equal and opposite upward force has to be absorbed by the upper floors.
Maybe you should go read Bazant's paper again.
Beachnut;
To my knowledge I have never mentioned Dr. Jones or thermite. Don't put words in my mouth. I am far more interested in Keane's and Hamilton's statements today on the CIA's destruction of tapes. Just makes you wonder what else was hidden. That is my beef. I basically don't believe a word of the 9/11 Commission.
To my knowledge I have never mentioned Dr. Jones or thermite. Don't put words in my mouth. I am far more interested in Keane's and Hamilton's statements today on the CIA's destruction of tapes. Just makes you wonder what else was hidden. That is my beef. I basically don't believe a word of the 9/11 Commission.
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How about replacing the wooden cube with a third piece of cake with an lit M80 in the middle?
Now that's what I'm talkin about.
OMG, the CIA destroyed tapes showing them beating the BEJEBERS out of guys! OMG, a smoking gun now!! Funny, your PhD (or did you make up your DR junk too) mind after 6 years finds the smoking gun of destroyed tapes! Too bad these tapes were made after 9/11 or it could be important. Wow. Amazing.
Oops. you are just a no plane person, I just posted your no plane statement. You see, you may not understand the things you have already said make you a no planer. Yes you are a no plane at the Pentagon, and at PA. Why, cause you said
So what does your expertise in chemistry say, with all those honors and such, we need another expert on thermite and can you expose the lies of Jones. I mean you have no idea if the stuff Jones made up after 4 years of being silent on 9/11 is real or fake?
I like you no plane stuff. Two planes proven to be crashed at the Pentagon and in PA, and you say that a plane did not crash. Got to admit, you have all the facts against you but your bravely state the panes did not crash there. Wow, is that you PhD stuff do the thinking or is it all you photography training?
So you do not believe Jones, but you have trouble with some reports, but you can't say what it is. You have a story of what really happen but you can't say, and now with the CIA destroyed tapes you know it was what?
It is raining in CA, is that a smoking gun too? 9/11 truth, can make a smoking gun out of most anything. Jones said the LAST nail is in the coffin for thermite. What is your nail?
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Beachnut,
It is late where I am, and I'm currently very busy completing a thesis for my fourth degree which is why I haven't participated in these forums for a few months. I can assure you that my credentials are not lies and as you know nothing about me, do not accuse me of being a liar. At this stage I don't really care what happens in the US, if you are gullible enough to believe the lies that are being fed to you then so be it. I however remain skeptical. Dr. O.
It is late where I am, and I'm currently very busy completing a thesis for my fourth degree which is why I haven't participated in these forums for a few months. I can assure you that my credentials are not lies and as you know nothing about me, do not accuse me of being a liar. At this stage I don't really care what happens in the US, if you are gullible enough to believe the lies that are being fed to you then so be it. I however remain skeptical. Dr. O.
Your ideas on the destroyed CIA tapes are junk. I hope your super degree thesis is going better. It is sad to see people with you training to be so inferior to lay people. Sad to see others college educated people fail to even back their lies up with facts.
I knew you have to go, we would not want to delay you Feb graduations. What happen, did you fail to walk and now you have to finish your thesis. I know, personal problems can delay the work! It happens.
But to say your thesis is more important than you proving 9/11 was an inside job is ironic! Funny guy.
It is not skeptical, it is called wrong. You need to practice the truth with your thesis due and all.
But you do have a history of wrong.
better go before you post some more wrong stuff, like the smoking gun CIA tape destruction. bye
You have posted a lot of stuff that is not idicative of a successful thesis, how do 9/11 truthers gain degrees when they can not make one rational concluson on 9/11? How can you make your thesis free of what ever bias makes you a 9/11 falase witnesses, a person who passes on lies and hearsay? How?
Since you had to go, good luck with your thesis, you will have a hard time if your research problems you have with 9/11 invade those required for your thesis.
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