Gravity Can't Do This!

reply to post by wmd_2008


Yes it can happen.

Pay attention to the details of what you are looking at.

Notice where the collapse starts, around the middle of the structure. Which means you have 50% falling on 50%, weaken the supports on the bottom 50% ahead of the collapse, and it will work. 15 floors falling on 95 floors will not work.

It's not me saying this it is physics, how many more time do I have to post this...Please read this and understand...

The Law of Action-Reaction (Revisited)

A collision is an interaction between two objects that have made contact (usually) with each other. As in any interaction, a collision results in a force being applied to the two colliding objects. Newton's laws of motion govern such collisions. In the second unit of The Physics Classroom, Newton's third law of motion was introduced and discussed. It was said that...

... in every interaction, there is a pair of forces acting on the two interacting objects. The size of the force on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. Forces always come in pairs - equal and opposite action-reaction force pairs.

This is fundamental physics, and the basis of classical mechanics.

Newton's third law of motion is naturally applied to collisions between two objects. In a collision between two objects, both objects experience forces that are equal in magnitude and opposite in direction. Such forces often cause one object to speed up (gain momentum) and the other object to slow down (lose momentum). According to Newton's third law, the forces on the two objects are equal in magnitude. While the forces are equal in magnitude and opposite in direction, the accelerations of the objects are not necessarily equal in magnitude. In accord with Newton's second law of motion, the acceleration of an object is dependent upon both force and mass. Thus, if the colliding objects have unequal mass, they will have unequal accelerations as a result of the contact force that results during the collision.

It's not me making these claims! They are well known, and accepted laws, that you can not change by misunderstanding them, or claiming they do not apply. We are supposed to be here denying ignorance, not embracing it.

Wait a sec.
I'm sure janitorial supply closets were located on every floor.
If some of those closets stored flammable liquids in, those containers would have produced the type "projectiles".

reply to post by ANOK


The mass falling on the first floor generates such a massive impact force the floor CANT provide an equal an opposite force because the floor connections have exceeded their load limit so the FLOOR FAILS!

That in turn will cause stability problems with the walls then it repeats next floor down this time with the mass of the floor that just failed.

You CANNOT load the connections above their load limit thats all that holds the floor in place!!!

A little section on angle iron and 2 no 5/8" bolts!

Newtons First LAW

The velocity of a body remains constant unless the body is acted upon by an external force

The floor the debris falls on is at rest UNTIL the external force moves it ie the DYNAMIC LOAD of the debris!

reply to post by wmd_2008

Newtons First LAW

The velocity of a body remains constant unless the body is acted upon by an external force

Funny that you mention that, because if an object in motion remains in motion until acted upon by an outside force, why did the top sections velocity not decrease when it was acted on by an outside force?
[atsimg]http://files.abovetopsecret.com/images/member/ecd9e86d7650.jpg[/atsimg] Wow that is one constant, unchanging velocity. Why did Newtons First Law of Motion not apply to the top section of the building? Those are universal concepts that apply to everything from a strand of hair to a falling building, so that means if it defied the laws of physics, it's impossible, at least according to the official story.

Originally posted by wmd_2008
reply to post by ANOK

 

The mass falling on the first floor generates such a massive impact force the floor CANT provide an equal an opposite force because the floor connections have exceeded their load limit so the FLOOR FAILS!

Keep repeating this does not make it fact. Again how many time do I have to repeat this, EQUAL & OPPOSITE REACTION. That massive impact is acting on BOTH the impacted AND the impacting floors, EQUALLY. The top was 15 floors the bottom 95, which has more mass? You do the math. Yes floors can fail, but that failure could not be complete, it would have to slow from loss of Ke to other energy, at least deformation, sound and heat, let alone friction/resistance which would cause the largest loss of Ke.

You CANNOT load the connections above their load limit thats all that holds the floor in place!!!

That is an assumption, where is the evidence that load limits were reached? Regardless, your reasoning is not taking into consideration what I just explained above, and have been trying to explain to you for awhile now.

Even IF it exceeded load limits, the collapse would still have to abide to the laws of motion, you can not get around that FACT.

Newtons First LAW

The velocity of a body remains constant unless the body is acted upon by an external force

Yes, and that external force is the rest of the building, no external force would be air. Why you think the lower part of the building did not put a force on the top section is beyond me. It had to do that for the building to ever stand in the first place. Your hypothesis ignores that there is still 95 intact floors bellow the 15 that is dropping.

The floor the debris falls on is at rest UNTIL the external force moves it ie the DYNAMIC LOAD of the debris!

And what about all the structure bellow the floor the debris is dropping on? You keep pretending it has no effect on the collapse, which is why your reasoning is wrong. THAT is an external force that will act on the falling mass, and reduce the Ke of the falling mass because it is converting that Ke to other energy needed to crush the floors, overcome friction/resistance, of which a byproduct of is heat and sound which also is an energy conversion from the Ke. If Ke is being continually lost as each floors impacts the collapse would slow and arrest.
15 floors falling on 95, you do the math.

You seem to want the opposite to have happened, where the lower structure was offering no resistance at all allowing falling floors to simply gain speed and mass, no loss of Ke, which is impossible.

You've seen this gif before, it shows the building is not doing what you claim...

reply to post by wmd_2008

The mass falling on the first floor generates such a massive impact force the floor CANT provide an equal an opposite force because the floor connections have exceeded their load limit

You really need to update your understanding of when Newtonian physics do and do not apply then take a fresh look at what the OS is claiming.

Equal and opposite reactions applied throughout the entire collapse, they were just very small to allow a 2/3rds free fall drop. The average crushing force the falling top section applied to the lower structure was about 1/3rd of its stationary weight. The equal and opposite average upwards resistance force was therefore also 1/3rd of the stationary weight of the top section (three times less than when it was holding the top section stationary).

The other implication of equal and opposite reactions is that at each floor impact, the only way for the connections on the lower floor to fail is if the connections on the upper floor impacting it also fail (since its connections are subjected to equal loading).

so the FLOOR FAILS!

That in turn will cause stability problems with the walls then it repeats next floor down

How would unrestraining the columns above the next impacted floor contribute to lessening the capacity of that floor? If anything it would make the system more flexible and allow it to absorb a larger amount of energy during the collision via the columns.

then it repeats next floor down this time with the mass of the floor that just failed.

Don't forget that in-order for it to collect a stationary mass the velocity must also decrease to conserve momentum. Severing connections slightly ahead of the collapse wave would reduce this requirement however.

The floor the debris falls on is at rest UNTIL the external force moves it ie the DYNAMIC LOAD of the debris!

Until a NET external force moves it. Don't forget to include the upwards force provided by the undamaged lower structure.

Originally posted by TupacShakur
because if an object in motion remains in motion until acted upon by an outside force, why did the top sections velocity not decrease when it was acted on by an outside force?

Why are you ignoring the external force of gravity?

You really have no understanding of physics!

reply to post by ANOK

Once again you are confusing weight with mass.

No you are the one who is confused.
On planet Earth Mass = Weight.

You can check it out here.
Unless you think the good people at New York University are lying to us.

A bug will never have more mass than a windshield, unless it's huge.

Once again you are confused. Mass equals weight around here.

As far as paint chips, do you realise how fast space debris is moving?

So you agree that velocity makes a difference?

The falling floors of the towers were not moving fast enough for their speed to be significant in increasing their mass, and overloading the larger mass.

Here is your greatest error. Yes the floors were moving fast enough.
Lets keep the numbers simple.

Gravity on Earth accelerates an object at 32 feet per second.

If we assume one floor collapses a distance of 16 feet, gravity will accelerate it to a speed of 22mph.
And if we assume the floor below can flex 3 inches before it gives way.

That would mean one ton of debris would exert 64 tons of mass on the floor below at impact.

You can run the numbers here.

So if the weight of the airplane debris alone (150tons) comes crashing down one floor the impact force is the equivalent of a Ticonderoga class missile cruiser resting on the floor.

The numbers add up very quickly. I know the distance between the floors was not 16 feet. But even if we cut the impact force in half it would still be a mass factor of 32 times normal.

No floor below could support 32 times the weight of the floor above. Let alone 2 floors above. Or 3 floors above.

Originally posted by DrinkYourDrug
reply to post by wmd_2008

 

The mass falling on the first floor generates such a massive impact force the floor CANT provide an equal an opposite force because the floor connections have exceeded their load limit

You really need to update your understanding of when Newtonian physics do and do not apply then take a fresh look at what the OS is claiming.

Equal and opposite reactions applied throughout the entire collapse, they were just very small to allow a 2/3rds free fall drop. The average crushing force the falling top section applied to the lower structure was about 1/3rd of its stationary weight. The equal and opposite average upwards resistance force was therefore also 1/3rd of the stationary weight of the top section (three times less than when it was holding the top section stationary).

The other implication of equal and opposite reactions is that at each floor impact, the only way for the connections on the lower floor to fail is if the connections on the upper floor impacting it also fail (since its connections are subjected to equal loading).

so the FLOOR FAILS!

That in turn will cause stability problems with the walls then it repeats next floor down

How would unrestraining the columns above the next impacted floor contribute to lessening the capacity of that floor? If anything it would make the system more flexible and allow it to absorb a larger amount of energy during the collision via the columns.

then it repeats next floor down this time with the mass of the floor that just failed.

Don't forget that in-order for it to collect a stationary mass the velocity must also decrease to conserve momentum. Severing connections slightly ahead of the collapse wave would reduce this requirement however.

The floor the debris falls on is at rest UNTIL the external force moves it ie the DYNAMIC LOAD of the debris!

Until a NET external force moves it. Don't forget to include the upwards force provided by the undamaged lower structure.

SORRY BUT YOU ARE WRONG.

I had to visit an engineer this morning regarding a project soon to start when we finished he showed me some funnies he had got on emails so I asked him about the loads in this situation and he said this.

The impact load would be considered as a MINIMUM of twice the static load of the falling mass it wouldn't be less but it could and probably would be way more than twice the static load depending on time taken for the slab to fail which he had no doubt would and did.

So for the North Tower that's the equivalent of 30 floors minimum and for the South Tower 60 floors minimum.

The bulk of the falling mass has to hit the floor slab and the only thing that can resist the imposed load is the connections as the floors are suspended between the walls and core.

He also commented on how the stability of the walls would be affected by the loss of the floor and impact from debris falling as well.

This engineer was a senior engineer for one of the biggest firms in the UK and now earns his living as an independent engineering consultant.

Looking forward to your reply.

Originally posted by ANOK

Keep repeating this does not make it fact. Again how many time do I have to repeat this, EQUAL & OPPOSITE REACTION. That massive impact is acting on BOTH the impacted AND the impacting floors, EQUALLY. The top was 15 floors the bottom 95, which has more mass?

What stupidity.

The top 15 floors were in motion. This is indisputable.

The bottom 95 floors DID NOT go into motion at the time of the first collision, nor at any time did the bottom section move as a whole as a result of these collisions.

This proves to all but the inept that the mass of the bottom 95 floors is not in play vis a vis slowing the falling mass. The only way that it could is if it also went into motion, and there is no load path capable of transferring the momentum of the top 15 floors to any columns capable of providing enough strength to stop it.

This is where truther understanding of physics fails. They are unable to differentiate from a horizontal collisions that they learned about in school, or more appropriately some website that they Googled, where both objects are put into motion and determining what kind of damage would ensue from it.... and the reality of what happens during a vertical collision like the collapses where the entirety of the objects aren't put into motion all at once.

It shows that truthers are either unable to understand, or more likely just enjoy trolling their lies.... when the rational side points out that stuff falls on a floor and sets it into motion... one at a time.

Yes, and that external force is the rest of the building, no external force would be air. Why you think the lower part of the building did not put a force on the top section is beyond me. It had to do that for the building to ever stand in the first place. Your hypothesis ignores that there is still 95 intact floors bellow the 15 that is dropping.

With no load path capable of transferring the available resistance to the larger mass. This is inescapable:

Stuff falls on floors > loads are transferred to columns through the connections > the connections fail WELL below the amount of resistance needed to decelerate the descending mass, at best it can only result in lesser acceleration > truthers don't understand the difference between deceleration and lesser acceleratrion > the discussion continues

And what about all the structure bellow the floor the debris is dropping on? You keep pretending it has no effect on the collapse, which is why your reasoning is wrong

There is no loiad path. Therefore, he is right and you are wrong.

If Ke is being continually lost as each floors impacts the collapse would slow and arrest.

Keep trolling this point please, for it is so utterly and laughably wrong that it seves the purpose to intelligent seekers of truth, like Cgarlie Veitch, to see that the TM is intellectually bankrupt.

Each collision only results in lesser acceleration, not a deceleration.

A deceleration would be required for the descending mass to arrest. However since it is generally agreed by any truthful person that the collapse front progressed at less than freefall acceleration (decreased acceleration) then this shows that there was in fact resistance.

Any claims of how it "should have arrested" at this point requires a looksee into connection strengths, etc... and no truther can do it.

You seem to want the opposite to have happened, where the lower structure was offering no resistance at all allowing falling floors to simply gain speed and mass, no loss of Ke, which is impossible.

I'd bet he is sticking to reality, and not some fantasy based belief of a truther.

I'd bet that he says that since it\\the collapse front progressed at less than freefall acceleration, there was in fact a measurable amount of resistance to the collapse, but truthers either don't understand or are just trolling, cuz as YOU had in your signature line previously, you don't necessarily believe what you type.

Originally posted by ANOK

Originally posted by WarminIndy
If a boulder is placed on the roof of my car, it will buckle from the weight...same boulder dropped even 2 stories high will cause much more damage. Now suppose that boulder were dropped 10 stories. I would think my car could not bear any weight under it. Now think of this, we all know bathtubs are on 2nd floors. But now suppose the bathtub is full of water and propelled from 3rd floor, it would crash through the 2nd floor, and then the 1st floor. But suppose that bathtub were full of fire and hurled into the house going 200 miles per hour. Would the house not catch on fire?

Again the higher you drop the rock the more force the rock will put on the car but ALSO more force will be put on the rock from the car. That is the equal opposite reaction law.

If your rock has more mass than the car roof then the roof will dent. If the rock has less mass than the roof then rock will break. How much the roof dents, or the rock breaks, depends on the difference in mass between the two objects. Velocity increases the force on BOTH objects, not just the car roof. You can never make a small mass go through a larger mass no matter how fast it is moving. For example a bug will not go through a windshield no matter how fast either is moving, the bug will always be splattered.

This is the question I've asked before and was not replied to, what experiences more force the bug or the windshield? If you answer that correctly you contradict your claims. I guess that's why none of you answer it.

Don't they teach this in high school anymore?

If a bug flies into a windshield and lands on it, it is not hurt. It is only when the car is moving that the bug is smashed.

There are always variables in every equation. I suppose Superman flying into a building would not make a difference, but a jumbo jet liner full of fuel, yes, that would make a difference.

Think for a moment how big a jet is, from top to bottom. Now think how wide it is from wing tip to wing tip. Now think about how long it is from nose to tail. But get this, unlike the car you want us to grasp in your image, the building is not the one that is moving.

It is funny though, in 2000 I watched a documentary on Nova about the Japanese firm that built the WTC. The designer stated that he designed it with only the wind as the main problem to overcome. When asked by the interviewer about why only wind, wasn't he worried about planes hitting it because it was so high? The man answered, "We don't think planes are going to hit it, that would be unreasonable to assume".

This documentary was out a year before 9/11, and the design flaw was not compensated for because they thought the event would never occur. Yes, the building designer admitted design flaw.

reply to post by ANOK


Look at this ANOK



The big red arrow is the load from above (ie the 15 floors) the little red arrows show what is resisting the load on the floor, yes the floor connections resist the load.

Now can you please show everyone how the floor below can help the floor above resist the load (the big red arrow)

The bulk of the falling debris would hit the floorslab look at my post above re impact load.

There is NO direct connection from one slab to another so the floors cant help a floor above them.

Any load that fell on wall columns WOULD have resistance from below but once the bracing effect of the floor slabs was taken away the walls lost stability its that simple!

Now hopefully even YOU can undestand the process!

reply to post by wmd_2008


You keep showing that pic, but you are missing the point wmd.

I have explained this before, even IF all the connections failed, the floors themselves as they stacked up would reduce the Ke of the falling mass due to friction/resistance, sound, heat, deformation etc. For your floors to continue crushing each other, and not slow down, Ke would have to increase, which is impossible.

If floors are not stacking up, where are they going wmd? I can tell you, they were being ejected, and when debris is ejected it is no longer acting on the vertical plain.

As I said before, the columns could have been toothpicks, and completely failed as the floors fell, but you would still have resistance as the floors stacked up. I there were no floors to stack up, there is no mass to do any crushing.

For once I'd like to see an explanation from you that actually includes the relevant physics like Newtons laws of motion. Explain how the equal opposite reaction law came into play etc.

Why won't you OSers answer this question?

While driving a car on the highway you hit a bug. The bug hit the windshield and the windshield hit the bug. Which of the two forces is greater? The force on the bug or the force on the windshield?

Originally posted by WarminIndy
If a bug flies into a windshield and lands on it, it is not hurt. It is only when the car is moving that the bug is smashed.

You're missing the point also lol. The question proves my point. The answer is the forces on both are the same, equal opposite reaction, and the reason the bug loses is MASS, not velocity. This is basic physics, didn't any of you go to school, or are you not old enough to have taken that class yet?

There are always variables in every equation. I suppose Superman flying into a building would not make a difference, but a jumbo jet liner full of fuel, yes, that would make a difference.

No, the laws of motion only break down at extremely high speed, and nano-particles. The laws apply regardless of how much fuel the plane had. But that isn't the issue, the issue is a building collapsing globally, symmetrically, through a path of increasing most resistance. The plane is relevant to that.

Yes, the building designer admitted design flaw.

Again, we are not discussing the planes impact so that 'flaw', as you call it, is irrelevant to my point.

Originally posted by samkent

Originally posted by ANOK
Once again you are confusing weight with mass.

No you are the one who is confused.
On planet Earth Mass = Weight.

samkent, it appears that remedial physics lessons are probably needed to help your misunderstanding here.

Try this experiment:
Take a set of scales into a stationary elevator. Stand on them and record your weight.
Now, while the elevator is accelerating, moving upwards, stand on the scales and record your weight.
Finally, while the elevator is decelerating, moving upwards, stand on the scales and record your weight.

Answer these two questions:
Did your mass change while you were in the elevator?
Did your weight change while you were in the elevator?

Now you tell me if that elevator was on planet Earth, or not...

Originally posted by wmd_2008
reply to post by ANOK

 

Look at this ANOK

The big red arrow is the load from above (ie the 15 floors) the little red arrows show what is resisting the load on the floor, yes the floor connections resist the load.

Now can you please show everyone how the floor below can help the floor above resist the load (the big red arrow)

The bulk of the falling debris would hit the floorslab look at my post above re impact load.

There is NO direct connection from one slab to another so the floors cant help a floor above them.

Any load that fell on wall columns WOULD have resistance from below but once the bracing effect of the floor slabs was taken away the walls lost stability its that simple!

Now hopefully even YOU can undestand the process!

So that side view shows ONE TRUSS. What was the total number of trusses and connections around the inner and outer perimeter of the floor assembly?

How could fire make them all give way simultaneously?

psik

Originally posted by ANOK
This is basic physics, didn't any of you go to school, or are you not old enough to have taken that class yet?

I think I am probably older than you. What you are presenting is something you believe is a constant, but yet it contains variables. And variable are always present in Algebra, Physics and Geometry. That darn x and y seem to never want to leave us alone.

Here is an equation...

(big building)(x) (what will bring it down)(y) = big building smashed on ground.

now figure it out using every constant you can think of....oh, wait, there are variables. darn, got to figure them out first.

I seem to recall that in 1989, a bomb was planted in the underground garage of the WTC and it only caused damage in the garage....and that was not major and did not bring it down.

reply to post by ANOK


With the start of the collaspe of the N Tower you had the equivalent of 15 floors of mass dropping one floor (around 12ft) that hit the floor below which failed.

You now have 16 floors of falling mass which guess what can now drop a floor (around 12 ft) now if the first floor couldn't survive 15 floors what make you think the next would survive 16 floors worth of mass.

All the floors had the same connections all the way to the bottom, the floor connections could only support there mass x the safety factor.

I spoke to an engineer today regarding this he said that the impact of a falling mass will generate twice repeat twice its static load and that is used as a minimum.

He said the actual impact force would be a lot more but you need to know either how quick the floor fails or the distance the impacting load travels before the impacted floor fails.

Also due to the design the walls loose stability once floors are lost.

What myself and others on here have been telling you for ages.

You keep looking at the literal meanings of words NO one has claimed that the falling floors all stay in one piece or all fall perfectly horizontally thats why we say mass of the falling floors etc.

The first impact would have been the equivalent of 30+ floors minimum for the north tower and 60+ floors for the south tower.

reply to post by psikeyhackr


Look at my reply to ANOK.

Ok...imagery again.

A balloon filled with air contains weight. When you push down on the balloon it smashes down. Now increase the amount of force applied to the balloon, it bursts.

If I drop a brick on the balloon, it bursts. We can say that the amount of empty space between the the floors would not buffer a load greater than the weight of the air. But that air in the spaces was sucked up toward the massive fire, leaving those empty spaces as a vacuum.Each floor then began to fall into that vacuum, and most of the things contained on that floor were on fire, and had burning jet fuel that weakened each successive floor support.

As each bit of the fire found new material to burn, the fire would get hotter. Have you ever seen a burning house or barn? When the roof catches fire, the walls are too weak to withstand the weight of the mass of fire as oxygen comes rushing in and the walls then collapse. We could say that the fire could go out leaving only ashes, but those ashes are not cooled even the next day and the collapsed building still smolders.

The WTC was actually a giant Lincoln Log structure with an outer covering made of concrete and glass.