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Old 2012-02-02, 10:28   Link #59
Arya
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Join Date: May 2004
Quote:
Originally Posted by warita View Post
Actually, this is something i wondered about in the past. Because what this mainly boils down to is the resistance of the air pressure against the weight... so the lighter the object, the greater the air pressure resistance on smaller weight.... hence the object is falling slowlier.

BUT!!!! A human body inside the elevator is not exposed to any flow of air during the fall, unlike the elevator. You have to remember, that the elevator is not falling from free sky but in narrow and tight shaft, which means that the air the falling elevator pushes downwards doesnt have the room to escape sideways and the resistance increases significantly. At the same time, the object inside the elevator (= the nurse) is falling in an inclosed space = she is falling together with the air enclosed inside the elevator. Her speed of decent is NOT decelarated by any air presure resistance.
I am not a physist and I cannot calculate, what the terminal speed of objetcs would be.... nor can I predict if the elevator would be falling faster or slower than the nurse. I know for sure though that due to the innertia force the nurse would probably separate from the elevator floor, but I doubt that her speed would be so much smaller that she would hit the ceiling...

So this is what I think would happen. Innitially due to innertia, you would separate from the floor and float during the fall. But I suspect that your own terminal velocity would be higher than that of the elevator, because you are not exposed to air rsistance while the elevator is... so slowly you would come back into the contact with the floor. But the question is, how many floors would the building have to have in order for that to happen? I have no idea, I just think that 7 floors might not be enough.
mmm, the first problem I see is that the elevator and the nurse start their fall at 0 speed. Speed that increase due to the gravity. But they both are submitted to the same acceleration. So in case there is some different in speed due to the air's resistance I'd say it were minimal. Anyways in the opposite way, I mean, if we assume that the nurse has less resistance her acceleration speed should be higher than the lift's, as you stated. So she would have always her feet on the lift ground and never float.
For a more scientific source, in zero-gravity simulations the aircraft must climb at a steep angle, level off, and then dive **. The Zero-G happens when the plane level off. So The floating to occur needs the carrier (airplane or elevator) to fly from down to up and not from up to down.


** quoted after googling.
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Last edited by Arya; 2012-02-02 at 10:33. Reason: The acceleration is costant
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