Has Anyone Seen A Realistice Explanation For Free Fall Of The Towers?

Status
Not open for further replies.
Arkan_Wolfshade said:
Err, would the ball from floor 110 need to strike the ball at 109 (to start 109's motion) if you're even trying to at all simulate the collapse; as the KE from floor/ball 110 is added to floor/ball 109 so floor/ball 109 accelerates faster (initially) than freefall? Or am I completely off base here?
Click to expand...

Yes, not to mention that balls 110 and 109 would have to hit 108, and so on down the line. Each time an initial velocity would be imparted to the ball being hit. And the force striking it would grow as the mass striking it grew.
 
kevin said:
Yes, not to mention that balls 110 and 109 would have to hit 108, and so on down the line. Each time an initial velocity would be imparted to the ball being hit. And the force striking it would grow as the mass striking it grew.
Click to expand...

I had an argument over this on the LC forum, and one of their guys even made a spreadsheet of my claims. I'll see if I can find it, although I have a suspicion it was in the skeptics forum.
 
Got it:

http://s15.invisionfree.com/Loose_Change_Forum/index.php?showtopic=6884&view=findpost&p=5603383

Although the link to the spreadsheet is gone. It took in account momentum from each floor hitting the next etc, and gave a collapse time of 15.5 seconds. I also suggested that 75% of the energy might be lost at each stage (I picked a big number), and this gave a collapse time of 20 seconds.

The formula wasn't perfect, and there's other stuff to take into account, like each floor didn't just collapse as the one above hit, but there could've been sections that cam down together, but it wasn't bad.


And holy carp! My warn level has been reduced to 2% after all this time. I think I might be able to post on there again, but I don't know if I should risk it and just get banned by JDX. Unless maybe I claim to have been swayed by their arguments and join the CT crowd, so I can get a look in the Pentagon FDR forum.

ETA: No, my posting permissions are still removed, so I remain in limbo over there.
 
Arkan_Wolfshade said:
Err, would the ball from floor 110 need to strike the ball at 109 (to start 109's motion) if you're even trying to at all simulate the collapse; as the KE from floor/ball 110 is added to floor/ball 109 so floor/ball 109 accelerates faster (initially) than freefall? Or am I completely off base here?
Click to expand...
Yes, you would need to consider that the balls get combined in order to simulate the collapse, which Judy didn't do. You would conserve momentum at the collision, not energy, and there would be energy leftover for things such as breaking the balls, and heat.

Here's something I just threw together in Excel. I'll try to explain a little what I did. In this billiard ball model, you can figure what speed it finishes at, based on the speed it started at, and the gravitational potential energy it acquires during its 12.3 foot fall. I apologize for the English units:

Vf = Sqrt( V0^2 + 2*g*h )

A close approximation of the time for each floor to fall would be the distance of 12.3 feet, divided by the average of the initial velocity and the ending velocity for that floor. This would be a little off for the first few floors, but would be pretty accurate through most of the fall. A good approximation for 110 floors.

The initial velocity for each floor would be the final velocity of the floor above it, adjusted down by the conservation of momentum of adding one more ball to the mass. For example, if 20 balls are falling at speed V from above, then by conservation of momentum the 21 balls should start their fall at V*20/21.

That's pretty much all you need to know, now just let Excel do the figuring floor-by-floor:
Code: 
floor	#balls	V0	Vf	Vavg	time	cuml. time
110	1	0.00	28.06	14.03	0.88	0.88
109	2	14.03	31.37	22.70	0.54	1.42
108	3	20.91	34.99	27.95	0.44	1.86
107	4	26.24	38.42	32.33	0.38	2.24
106	5	30.73	41.62	36.18	0.34	2.58
105	6	34.68	44.61	39.64	0.31	2.89

...

7	104	164.00	166.39	165.20	0.07	14.54
6	105	164.80	167.17	165.99	0.07	14.62
5	106	165.60	167.96	166.78	0.07	14.69
4	107	166.39	168.74	167.56	0.07	14.76
3	108	167.17	169.51	168.34	0.07	14.84
2	109	167.96	170.28	169.12	0.07	14.91
1	110	168.74	171.05	169.89	0.07	14.98

So by this model, the collapse should have taken 15 seconds, with plenty of energy left over for destroying the material. This kind of analysis is not hard to do, but I guess beyond the grasp of a PhD in ME.
 
By the way, this simple model is assuming that the collapse started with floor 110. If it started at 88, or 70, it would change the results. That would get a little more complicated, but anyone competent in classical physics should be able to do that in a couple of hours. Maybe that's too much time for the "scholars" to invest in a "peer-reviewed" journal. Or maybe, just maybe, they're not competent in classical physics.
 
Belz... said:
3" rebar on 4' centers
Click to expand...

I was digging around the NIST report and ran into a diagram of the floor truss that had an interesting number in it.

578944d8c5ecbb3db.png


Notice the truss rod penetrates the concrete at 3'-4" centers. I think that's as close to having a right number as he is going to get. Of course the units are wrong. And this is the floor not a wall. And the rod is only 1" thick. But hey, close enough for CT work.
 
T.A.M. said:
http://video.google.ca/videoplay?docid=65460757734339444&q=9/11+eyewitness

sorry i misquoted the name, it is 9/11 witness.

Video 2 of 3... from around th 6:30 to 7:30 mark
Click to expand...

Not to stray too far offtopic here, but another interesting thing to note on that video is how badly WTC7 is pelted with debris from WTC1. While you can't actually see the piece hit, there is a very large chunk of debris that is falling with a trajectory that is obviously going to cream WTC7 dead on.

Back on topic, it's also interesting to note that there is a large chunk of facade that falls rather quickly, I'd say approx 9-10 seconds from the collapse initiation to it disappearing - close to freefall estimates - far ahead of the rest of the tower.

Yet they still claim WTC1 came down at freefall (or faster) speeds. Were there two sets of gravitational fields at the WTC Complex?

-Joytown
 
skeptigirl said:
NOVA - Why the Towers Fell

Nuff said.
Click to expand...

As an addendum to this, I posted this in the LC3 thread, but I'm sure it got buried, there's an new NOVA program called "Building on Ground Zero" that follows onto Why the Towers Fell

From an L.A. Time article:
One reason PBS decided to revisit its 2002 documentary on "Why the Towers Fell" with "Building on Ground Zero" (which is scheduled to air Sept. 5) is new technical information that has surfaced on the causes of the towers' collapse, said Paula Apsell, the senior executive producer of "Nova." Because information contained in the first documentary was used to revise building codes, the corrections need to be reported, she said
Click to expand...

(Source: http://www.latimes.com/entertainmen...alk28jul28,1,6957507.story?coll=la-entnews-tv )

Be interesting to see what new information it provides.

-Joytown
 
One of them was 'cause Frodo managed to get the Ring back in Mt. Doom. I think the other one is still supposed to be standing - at least at the end of the movie.
 
fuelair said:
One of them was 'cause Frodo managed to get the Ring back in Mt. Doom. I think the other one is still supposed to be standing - at least at the end of the movie.
Click to expand...
and the other was attcked by trees.....and judy wood says the towers were like trees....judy WOOD...trees....OMG!!! IT ALL MAKES SENSE!!!!!!!!!
 
And the Yoo Ess Gummint secretly has been bugging people's phone lines -- the study of bugs is entomology -- ENT-omology... It all fits.
 
And the giant EAGLES that come in and rescue the evil covert operatives Frodo and Sam before anyone knows...

EAGLES. AMERICA. OMFG BLACK HELICOPTERS!!!!1111

AND who write it all, huh? JRR TOLKIEN! TOLKIEN? Don't you mean TONKIN? False flag!!!!!!!!!!!!!!!!

TEH CONSPIRAT0R@!

Ahem.

-Andrew
 
Gee... I hope Christophera hasn't copied and pasted these "arguments" to the LC forums or whatever. Given the lack of critical thinking skills -- worse even than my own, which are pretty feeble -- in evidence, I can't help thinking someone might believe there's some truth to them. =>_<=

Every time I think I've come up with a claim too absurd for any being above the level of -- oh, say, clams or ginkgo fruit -- to believe, it turns out someone's already thought of it... and sometimes they're making money off it.
 
Hey, If You can't Find Raw Evidence Then Post Whatever.

kevin said:
I was digging around the NIST report and ran into a diagram of the floor truss that had an interesting number in it.

[qimg]http://www.internationalskeptics.com/forums/imagehost/578944d8c5ecbb3db.png[/qimg]

Notice the truss rod penetrates the concrete at 3'-4" centers. I think that's as close to having a right number as he is going to get. Of course the units are wrong. And this is the floor not a wall. And the rod is only 1" thick. But hey, close enough for CT work.
Click to expand...

Sad that you don't have any real evidence.

Here is an image showing what can only be the 3" HIGH TENSILE STEEL REBAR ON 4' CENTERS from the 1990 documentary called "Construction of the Twin Towers."
 
Christophera said:
Sad that you don't have any real evidence.

Here is an image showing what can only be the 3" HIGH TENSILE STEEL REBAR ON 4' CENTERS from the 1990 documentary called "Construction of the Twin Towers."
Click to expand...
You're crazy, it's perfectly clear in that picture the the rebar 2.5" and on 3'6" centers. Anyone who can't see that is either blind, a government shill, or their underwear is riding up.
 
Status
Not open for further replies.

Back
Top Bottom