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Re: 9-11 Wackos

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Momentum= MassxVelocity

In the the collapse, Mass increased at each floor  and velocity was increasing as well

On 5/25/07, Gerard Madden, SE < gmse4603(--nospam--at)> wrote:
wouldn't it be gaining momentum at each floor? afterall, the shearing of the floor from the impact of the (oh I don't know say 20 stories of floor from above) takes a millisecond to break when you reach the next floor with now 21 floors coming down there is that much more has to have to be stopped and the momentum resistance strength creates less and less drag due to the force increase (MASSxACCELERATION). Gravity is acting in the same direction as the movement of the mass, so it's not a text book example in college text book of perfect or idealized assumption of elasticity.


On 5/25/07, ECVAl3(--nospam--at) <ECVAl3(--nospam--at)> wrote:
In a message dated 5/25/2007 10:33:37 A.M. Pacific Daylight Time, gmse4603(--nospam--at) writes:
Freefall: mass and ever increasing mass (each floor falling on another) and acceleration (those things were too heavy to reach terminal speed from wind resistance) ...makes perfect sense to me.
Maybe I just don't get it but, in my mind, when an object in motion meets a stationary object, there is a lose of momentum thereby slowing down the acceleration process. Is this wrong? I'm still puzzled as to how the WTC towers collapsed at nearly the same time as an object in freefall would take to fall the same distance.
S.Macie, P.E.

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