How do you explain the speed of the fall of WTC?

Question

I mean the buildings fell faster than free fall.

Source:
http://www.youtube.com/watch?v=Ml_n5gJgQ_U

Did anyone watch the video in the link?

Only few bothered to give answers. The others started to insult.

Noname: A black hole would pull the building a lot faster. 1g is the acceleration of gravity
B=mg is the type of the gravity force.
h=1/2 gt2 is the type of distance and time.
g=9.81m/sec2
Do your science now. Does it add up?

Answer 1

The near-freefall speed of the fall for the WTC towers is indeed an issue, despite what you've read in official government documents. The energy of deformation for the floors being hit by building mass from above is only one consideration. Another is inertia.

The notion that the downward falling mass would not even be slowed by the cumulatively even larger mass below, which was initially stationary, is ridiculous. Suppose you put some Super Dooper Glue on two baseballs, took one of them off a ways, and threw it at 60 mph at the other baseball, which initially was stationary with respect to the ground. They hit dead-center in a collision, which, because of the Super Dooper Glue, is perfectly inelastic. Do the two balls...

A. Continue to travel in the same direction at 60 mph?
B. Continue to travel in the same direction at 30 mph?

The answer is B. The inertia of the initially stationary ball slows the combined mass. Some of the energy is lost just getting the initially stationary mass moving. The energy lost doing that comes out of the thrown ball's speed. It would not matter if, instead of one initially stationary ball, there were several smaller balls that got hit dead center in perfectly inelastic collisions: as long as the total mass of the smaller balls added up to the mass of a baseball, the same reasoning applies.

So, to get back to the WTC towers, not only would the energy of deformation take out a chunk of the falling mass's speed, the inertia of initially stationary floors would, cumulatively, also take out further chunks of the falling speed. Gravity would eventually replace that speed, but the time consumed by the losses of speed remains elapsed, and the result would be a longer-than-freefall time collapse for both buildings.

Since both of the WTC towers fell at almost the freefall speed, it means that the floors below were already falling when the mass above caught up with them.

There's more evidence in favor of demolitions, of course. The concrete powder is probably the most significant and easy to understand. A fall from a height does not transform concrete slabs into powder. It breaks them into chunks. Only explosives detonated within the concrete while the concrete was still at an elevation relative to the surrounding city buildings would have produced the scattering of concrete powder observed after the tower collapses. Explosives imply demolition, which implies an inside job.

It ought to be common sense that one doesn't rely on a suspect in a crime to be honest in revealing the facts of that crime. After all, the US government has killed Americans and lied about it before.

http://answers.yahoo.com/question/index?qid=20061220093635AAspZWV

Answer 2

Congratulations,this is officially the stupidest question of the day! Faster than free fall? Do you know what the term free fall even means,please back to elementary school until you understand the basics.

AD

Answer 3

It is impossible for them to fall faster than free fall. Even if there was a black hole under them, they could not fall faster than free fall.

You need to study some science.

Answer 4

6. How could the WTC towers collapse in only 11 seconds (WTC 1) and 9 seconds (WTC 2)—speeds that approximate that of a ball dropped from similar height in a vacuum (with no air resistance)?

NIST estimated the elapsed times for the first exterior panels to strike the ground after the collapse initiated in each of the towers to be approximately 11 seconds for WTC 1 and approximately 9 seconds for WTC 2. These elapsed times were based on: (1) precise timing of the initiation of collapse from video evidence, and (2) ground motion (seismic) signals recorded at Palisades, N.Y., that also were precisely time-calibrated for wave transmission times from lower Manhattan (see NCSTAR 1-5A).

As documented in Section 6.14.4 of NIST NCSTAR 1, these collapse times show that:

“… the structure below the level of collapse initiation offered minimal resistance to the falling building mass at and above the impact zone. The potential energy released by the downward movement of the large building mass far exceeded the capacity of the intact structure below to absorb that energy through energy of deformation.

Since the stories below the level of collapse initiation provided little resistance to the tremendous energy released by the falling building mass, the building section above came down essentially in free fall, as seen in videos. As the stories below sequentially failed, the falling mass increased, further increasing the demand on the floors below, which were unable to arrest the moving mass.”

In other words, the momentum (which equals mass times velocity) of the 12 to 28 stories (WTC 1 and WTC 2, respectively) falling on the supporting structure below (which was designed to support only the static weight of the floors above and not any dynamic effects due to the downward momentum) so greatly exceeded the strength capacity of the structure below that it (the structure below) was unable to stop or even to slow the falling mass. The downward momentum felt by each successive lower floor was even larger due to the increasing mass.

From video evidence, significant portions of the cores of both buildings (roughly 60 stories of WTC 1 and 40 stories of WTC 2) are known to have stood 15 to 25 seconds after collapse initiation before they, too, began to collapse. Neither the duration of the seismic records nor video evidence (due to obstruction of view caused by debris clouds) are reliable indicators of the total time it took for each building to collapse completely.

Answer 5

They fell slower than free fall.

Answer 6

Rosie say Gravity, first time in history that Gravity happened........

Answer 7

These links should clear things up for you.

http://www.911myths.com/index.html
http://gunstuff.com/america-attacked.html

9/11 was not an inside job.

Answer 8

I'll bet that REAL engineers know that answer. Those paid fools from moveon.org did not.

Answer 9

Res ipsa loquitor.

Answer 10

the sheer heat from the A/C fuel tanks.