[Chemistry4me]

So you're saying there were also terrorists at the bottom of the buildings and they detonated the bombs when the plane crashed? Or maybe there were just bombs put into place? [][]

[L_D]

So you're saying there were also terrorists at the bottom of the buildings and they detonated the bombs when the plane crashed? Or maybe there were just bombs put into place? [][]

I only have time for a very quick reply, most people who have looked at all the evidence and concluded that explosives HAD to have been used to bring WTCs 1 2 and 7 down as quick and completely as they did, also believe that the buildings were pre-laced for complete demolition, hence the saying "9/11 was an inside job".

Google 9/11truth and you will find thousands of websites on the subject, both for and against.

The planes and supposed terrorists were nothing more than a sideshow to the false flag operation that 9/11 was, and were inconsequential to the collapses that occured that day (most would also believe that the planes were remotely flown into the buildings and the supposed terrorists were just patsies).

[psikeyhackr (OP)]

So are you and psikeyhackr on the same page here about this WTC business? Except you seem to have a theory that they were blown up! Or is that just my misunderstanding? []

I am not talking about what caused the buildings to come down.

I am saying that if planes, fire and gravity are all that caused the WTC1 and WTC2 to come down then it should be possible to analyze and explain everything almost second by second from impact through collapse with all of the computing power we have today.

The Empire State Building was completed 70 years before the WTC was destroyed.  What kind of electronic computers did they have back then?  Skyscrapers must hold themselves up and withstand the wind therefore the designers must determine how much steel and concrete to put on every level.  Therefore how can a SCIENTIFIC ANALYSIS be done without that information?

Science is not about BELIEVING. Science is about KNOWING.  People that want to dismiss this as unscientific but haven't been DEMANDING to know the TONS of STEEL and TONS of CONCRETE on every level of the towers for the last SEVEN YEARS are full of crap.  Those so called architects and engineers at AE911TRUTH haven't been talking about that .  I have emailed them twice.

I have been to one of Richard Gage's seminars.  It comes across as propaganda rather than science to me.

psik

[wolfekeeper]

WRT Conservation of Momentum and the collapse of the Towers, if you could remove all the columns and just have the floors magically hovering until they were impacted then the mass alone of the hovering floors would still slow the collapsing mass more than what happened on 9/11.

If it couldn't physically fall down even if the columns had been removed by explosive (yeah, right) then how did it get to flat from up?

So you're saying that it was collapsed by an alien force field or invisible rockets? Or was it all a giant hologram? Perhaps it never actually fell down at all?

You're not making any sense at all.

[Chemistry4me]

You want a petition signed Mr. psikeyhackr?

[psikeyhackr (OP)]

You want a petition signed Mr. psikeyhackr?

Do the laws of physics give a damn about a petition?

This ain't politics.  This is PHYSICS!!!

Do you understand why the distribution of steel and concrete in the WTC  is important to analyzing the supposed collapse or not?  Are you interested in SCIENCE or not?

So do we expect high school kids to BELIEVE airliners could bring down the towers or UNDERSTAND why they could not?  9/11 is such a global event it involves global education.

http://911research.wtc7.net/materials/contrib/911_physics_v9a.htm

I have been to a website where I read a post by somebody complaining about science education in New Zealand.

psik

[Chemistry4me]

Alright alright, just calm down matey. Of course I understand.

[psikeyhackr (OP)]

Alright alright, just calm down matey. Of course I understand.

WHAT?  I'm always calm it's one of those Vulcan things.

Actually I'd like to beat a lot of these so called Truthers over the head.  With them running around screaming INSIDE JOB and talking about JFK and Pearl Harbor.

Science is a TRUTH MOVEMENT.

Grade school kids all over the planet should be laughing at engineers in the United States.

psik

[psikeyhackr (OP)]

There is something very curious about the nitwits in authority.

If you download the 10,000 page NCSTAR1 report and search it for "conservation of momentum" you will only find two occurrences.

In one case it refers to the analysis of air flow in a fire.  In the other case it is about the effect of the airliner impact on the trusses supporting the floor slabs. 

But about the ALL IMPORTANT effect of conservation of momentum on the overall collapse of the entire building they say nothing.  How  do you explain people claiming to be world renowned experts ignoring the obvious?

Didn't anybody like Cartoon Physics?   []

psik

[psikeyhackr (OP)]

More views but no responses in a week.

Fall of Physics

The people who claim the WTC towers underwent a gravitational collapse seem to exaggerate what gravity can do. This is a table showing the velocity and distance fallen by an object from a stationary start. In the first 1/10th of a second the mass moves less than 2 inches and is only traveling at 3.2 ft/sec. So a gravitational collapse of the WTC meant the falling top portion must have accelerated what it struck much more than gravity could have and also have broken whatever was supporting that intact portion of the building.

Code: [Select]

.           v == initial velocity
    Time    V = at + v     D = 1/2 at^2 + vt
               v = 0
    00.1     3.2 ft/sec    0.16 ft   1.92 in.
    00.2     6.4 ft/sec    0.64 ft   7.68 in.
    00.3     9.6 ft/sec    1.44 ft  17.28 1n.
    00.4    12.8 ft/sec    2.56 ft
    00.5    16.0 ft/sec    4.00 ft
    00.6    19.2 ft/sec    5.76 ft
    00.7    22.4 ft/sec    7.84 ft
    00.8    25.6 ft/sec   10.24 ft
    00.9    28.8 ft/sec   12.96 ft
    01.0    32.0 ft/sec   16.00 ft
    01.1    35.2 ft/sec   19.36 ft
    01.2    38.4 ft/sec   23.04 ft
    01.3    41.6 ft/sec   27.04 ft
    01.4    44.8 ft/sec   31.36 ft
    01.5    48.0 ft/sec   36.00 ft
    01.6    51.2 ft/sec   40.96 ft
    01.7    54.4 ft/sec   46.24 ft
    01.8    57.6 ft/sec   51.84 ft
    01.9    60.8 ft/sec   57.76 ft
    02.0    64.0 ft/sec   64.00 ft
No matter what brought the towers down the conservation of momentum cannot have been violated. This is the equation for an inelastic collision in which two masses stick together. If the second mass is stationary then v2 is zero.

Conservation of Momentum:

(m1 * v1) + (m2 * v2) = (m1 + m2) * v3

This means the ratio of the stationary mass to the impact mass greatly affects the resulting velocity. If the impact mass is smaller then it will be slowed considerably, but in the opposite case the velocity of the stationary mass will change a lot. But in a gravitational collapse there will be the additional effect of gravitational acceleration before and after impact.

So I have done the calculations for 3 "magical" cases. In each case four masses are magically suspended and when struck from above each mass is released with no resistance. In case #1 the 4 masses are are equal, 2.5 tons each. In case #2 the masses are in the sequence 1, 2, 3 and 4 tons from top to bottom. Case #3 is the reverse sequence of 4, 3, 2 and 1 ton. When the masses are struck from above they begin moving on the basis of conservation of momentum and undergo gravitational acceleration until the next object is struck. Case #0 is just a 10 ton mass dropped from 64 feet with no impacts and is used as a reference case.

Code: [Select]


 .            mass 1     mass 2      mass 3        mass 4
             64 feet   feet 48      feet 32      feet 16
                 
    Case 0    10 ton      0            0            0
    speed       0        32          45.25        55.43         64 ft/sec     
    time        0         1           1.41         1.73         2 sec

    Case 1    2.5 ton    2.5          2.5          2.5
    speed       0       32 16     35.78 23.85  39.91 29.93      43.82 ft/sec
    time        0         1       1.618 14%     2.12 23%       2.554 sec 28%

    Case 2    1 ton       2            3            4
    speed       0       32 10.67  33.74 16.87  36.17 21.70      38.66 ft/sec
    time        0         1       1.721 22%    2.324 34%       2.854 sec 43%

    Case 3    4 ton       3            2            1
    speed       0       32 18.29  37.35 29.05  43.23 38.91      50.37 ft/sec
    time        0         1        1.58 12%    2.023 17%       2.381 sec 19%


The Case line specifies the weight of mass at each of the 4 heights, 64, 48, 32 and 16 feet. These heights were chosen because they correspond to the "1/2 * 32 feet/sec^2" that is in the distance from acceleration equation thereby making calculations easier.

The speed line has the velocity of the net mass before and after impact based on conservation of momentum.

The time line has the time for the mass to fall to that point and the percentage difference from Case 0.

A body in freefall dropped from the top of the World Trade Center would have taken 9.2 seconds to reach the ground. The NIST says the tower that took longer to collapse did it in 11 seconds. So that is only 20% longer than the freefall time. But the WTC collapses required that the tens of thousands of tons of steel and concrete which had held up the buildings for 28 years be bent and broken and crushed. So how is it that only my absurd and miraculous collapse with inverted masses and disappearing supports comes down that fast in relation to freefall? A skyscraper must be bottom heavy and Case #2 using that distribution has double that percentage of time but it didn't require kinetic energy be used to break supports.

So what is the story with all of these people that claim there was a gravitational collapse but also pretend that knowing the TONS of STEEL and TONS of CONCRETE on every level isn't necessary? I have demonstrated that changing the distribution of mass alters the collapse time regardless of the strength of the material involved and how much kinetic energy would be required to break it.

Time and velocity calculations after impacts:

Code: [Select]


.   After Impact #1:
    Case 1: 16 = 16t^2 + 16t     1 = t^2 + t          t = 0.618  19.78+16
    Case 2: 16 = 16t^2 + 10.67t  1 = t^2 + 0.666875t  t = 0.721  23.07+10.67
    Case 3: 16 = 16t^2 + 18.29t  1 = t^2 + 1.143125t  t = 0.58   18.56+18.79

    After Impact #2:
    Case 1: 16 = 16t^2 + 23.85t  1 = t^2 + 1.490625t  t = 0.502  16.06+23.85
    Case 2: 16 = 16t^2 + 16.87t  1 = t^2 + 1.054375t  t = 0.603  19.30+16.87
    Case 3: 16 = 16t^2 + 29.05t  1 = t^2 + 1.815625t  t = 0.443  14.18+29.05

    After Impact #3:
    Case 1: 16 = 16t^2 + 29.93t  1 = t^2 + 1.870781t  t = 0.434  13.89+29.93
    Case 2: 16 = 16t^2 + 21.70t  1 = t^2 + 1.35625t   t = 0.53   16.96+21.70
    Case 3: 16 = 16t^2 + 38.91t  1 = t^2 + 2.431875t  t = 0.358  11.46+38.91
http://www.richarddawkins.net/forum/viewtopic.php?p=1058903#p1058903

No one on richarddawkins.net has found any flaws in the math since July of 2008, not even the man claiming to be a structural engineer.  He just complained about left brained physics.  LOL

Actually I think the people have chosen to BELIEVE the Officail Conspiracy Theory have chosen to ignore this.

psik

[wolfekeeper]

The examples you've calculated are the wrong ones.

You need to calculate the case with 1,2,4,8 or other exponentially increasing masses. That's what the mass in the WTC did- all really tall buildings have (more or less)an exponentially increase in the mass as you go down the building. The counterintuitive result with exponentially increasing masses is that if the collapse starts, it (nearly always) carries on.

(The reason it's exponential is that if you make it exponential, then it's possible to make the building almost infinitely tall in principle- in practice it eventually gets spindly enough that it gets unusably thin, so they stop.)

[psikeyhackr (OP)]

The examples you've calculated are the wrong ones.

You need to calculate the case with 1,2,4,8 or other exponentially increasing masses. That's what the mass in the WTC did-

Oh really?  And what do you think that would accomplish?

What do you think the point of my calculations was?

The linear sequence with the heaviest mass at the top took 19% longer than free fall.  The constant sequence took 28% longer than free fall.  The linear sequence with the heaviest mass at the bottom took 43% longer than free fall.

So the sequence you are suggesting would have to take even longer.  It is commonly said that the north tower came down in 11 seconds which is only 20% longer than the free fall time.  My objective was to demonstrate that conservation of momentum alone would slow a top down collapse caused by the plane such that everyone should recognize that it could not have occurred.

So you are helping me win the war by claiming to have beaten me at a skirmish.  Your assistance is most welcomed.

psik

[wolfekeeper]

Uh huh. So you presumably did the calculation and it didn't work.

It's all nonsense anyway; the building did fall down in the time that is showed on the video.

I don't care what calculation you can show that says otherwise; it fell down in that particular time. If your calculation says otherwise, your calculation is wrong.

The other thing you're failing to consider is that the structural failure happened at the speed of sound in steel. That's 4.5 km/s, so the entire metal structure can fail in the time that it takes the shock wave to travel the length of the building; very short. Basically the whole top few floors of the building acts as a pile drive and after falling onto the bottom section, the whole structure will fail in about a tenth of a second, then it's just gravity acting; everything just falls together.

[psikeyhackr (OP)]

Uh huh. So you presumably did the calculation and it didn't work.

It's all nonsense anyway; the building did fall down in the time that is showed on the video.

I don't care what calculation you can show that says otherwise; it fell down in that particular time. If your calculation says otherwise, your calculation is wrong.

You can presume whatever you like.  I didn't bother doing the calculations.  The larger the stationary mass the more it slows down the mass falling on it.

I am not disputing the collapse time.  I am just pointing out the IMPOSSIBILITY of it being a top down collapse without something destroying the supports to make it happen in that time frame.

psik

[L_D]

It's all nonsense anyway; the building did fall down in the time that is showed on the video.

I don't care what calculation you can show that says otherwise; it fell down in that particular time. If your calculation says otherwise, your calculation is wrong.

The other thing you're failing to consider is that the structural failure happened at the speed of sound in steel. That's 4.5 km/s, so the entire metal structure can fail in the time that it takes the shock wave to travel the length of the building; very short. Basically the whole top few floors of the building acts as a pile drive and after falling onto the bottom section, the whole structure will fail in about a tenth of a second, then it's just gravity acting; everything just falls together.

The upper portions of these buildings are approx 1/5 the mass of the lower portions, if anything is going to be smashed on impact it will be the weak upper portion, not the stronger undamaged lower portions. Also even if a shock wave were to somehow have destroyed the lower portion on impact then the collapse should represent that, rather than the progressive type of collapses we see.


With regard to earlier discussion of the mass of the building increasing lower down, I'm pretty sure it is only the steel columns that get bigger and thicker, the concrete and steel girders for the floors are uniform throughout the whole building.

 

[wolfekeeper]

It's all nonsense anyway; the building did fall down in the time that is showed on the video.

I don't care what calculation you can show that says otherwise; it fell down in that particular time. If your calculation says otherwise, your calculation is wrong.

The other thing you're failing to consider is that the structural failure happened at the speed of sound in steel. That's 4.5 km/s, so the entire metal structure can fail in the time that it takes the shock wave to travel the length of the building; very short. Basically the whole top few floors of the building acts as a pile drive and after falling onto the bottom section, the whole structure will fail in about a tenth of a second, then it's just gravity acting; everything just falls together.

The upper portions of these buildings are approx 1/5 the mass of the lower portions, if anything is going to be smashed on impact it will be the weak upper portion, not the stronger undamaged lower portions.

Nope, you've still missed the point.

If, for example the mass of the building goes 1,2,4,8,16

and 1,2 falls onto 4, and 4 is designed to withstand 50% at dynamic overload, let's assume that floor 1 and 2 acts as if it was twice as heavy when it impacts (due to momentum), then 4 will immediately fail and then 1,2,4 will fall onto 8, which will immediately fail and so on; the percentage overload *increases* as the failure propagates  1+2+4/8 is 7/8 whereas 1+2/4 is only 3/4.

With regard to earlier discussion of the mass of the building increasing lower down, I'm pretty sure it is only the steel columns that get bigger and thicker, the concrete and steel girders for the floors are uniform throughout the whole building.

Probably, but it doesn't matter; the total mass still goes up exponentially along the length of the building.

[psikeyhackr (OP)]

If, for example the mass of the building goes 1,2,4,8,16

and 1,2 falls onto 4, and 4 is designed to withstand 50% at dynamic overload, let's assume that floor 1 and 2 acts as if it was twice as heavy when it impacts (due to momentum), then 4 will immediately fail and then 1,2,4 will fall onto 8, which will immediately fail and so on; the percentage overload *increases* as the failure propagates  1+2+4/8 is 7/8 whereas 1+2/4 is only 3/4.
Probably, but it doesn't matter; the total mass still goes up exponentially along the length of the building.

Then you missed the point of my gravitational collapse calculations.

DYNAMIC OVERLOAD has nothing whatsoever to do with those collapse times.  I said the masses were held up by MAGIC and moved the instant they were hit from above.  There were no supports to overload.  So the distribution of mass that you propose would just fall even more slowly than mine because you increase mass more than I do.

The conservation of momentum and the energy required to break the supports are two separate factors.  That is why I did drops on toothpicks without washers to show the breakage effect without mass.  It is difficult to support masses by magic in real life.

psik

[wolfekeeper]

You haven't even attempted to scale things appropriately.

I'm sorry but your simulation is simply nonsense, it is so very far removed from the real mass distribution, strength and speeds of the WTC that you can draw no conclusions at all.

[psikeyhackr (OP)]

You haven't even attempted to scale things appropriately.

I'm sorry but your simulation is simply nonsense, it is so very far removed from the real mass distribution, strength and speeds of the WTC that you can draw no conclusions at all.

If you watch both of my videos

You will notice that I have frames that ask about the tons of steel and tons of concrete on every level of the towers.

I did not try to build scaled models.  How can you build scaled models demonstrating the physics if you don't have the distribution of mass data on the subject?  The purpose of my designs was to demonstrate that the material that we do not have accurate information on had to affect what happened.

It doesn't even make sense to have an investigation without information that simple.  The NCSTAR1 report doesn't even specify the total quantity of concrete in the towers.

So you are correct in that it is not scaled.  I never claimed it was.  But the models are built to be variable and my collapse demonstrated that stationary masses slow the falling mass down.  But the strength of toothpicks in my collapse demonstration is constant while a real skyscraper must get stronger and heavier all of the way down.

Your complaint is silly.

psik

[wolfekeeper]

How can you build scaled models demonstrating the physics if you don't have the distribution of mass data on the subject?

Yes that would be impossible to determine, and there are no resources that you can draw on.