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Re: lost msg: Re: bad-faith argumentation (was *earth* vs. *wing*)



How do you know that the quoted formula is correct
when the area/d --> infinity? (Area of the circular plate,
divided by the distance from the bottom does become
extremely large at the last moment of the fall.)

I assume that the weight in your formula refers to the
plate; the weight of the cage is negligible. Air density
should also be involved but the quoted formula has no
place for it, only the linear 1-a/g factor. What is the
origin of this formula? Would it be applicable in water?

David_Anderson wrote:

Ok to be exact, measure the acceleration of the plate, "a" and the
reduction in weight will be on the order of:

reduction= weight(g-a)/g

where g is the acceleration of gravity.
This assumes that the bottom of the cage is large with respect to the size
of the plate and the distance that the plate is to fall. I'm also not
getting into the problem of small transient effects.

David Anderson
dfa@fnal.gov

On Tue, 24 Aug 1999, Ludwik Kowalski wrote:

Referring to a flat plate ("parachute") accelerating in a cage
standing on a scale, David_Anderson wrote:

The scale would read a reduced weight as the plate dropped, just as a
diving board goes up when you step off of it. Unlike the birds in the
cage, the plate is in (almost) freefall and does not have a supporting
force.

Hmmm, but it keeps compressing air and pushing it toward the scale.