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Re: MATH PHYSICS



You're missing low velocity viscous drag, as used in analyzing the
Millikan oil-drop experiment. See chapter 12 of "The Mechanical Universe"
(standard edition).
Regards,
Jack

On Mon, 26 Nov 2001, Brian Whatcott wrote:

David Abineri wrote:

If one assumes that a projectile encounters an air resistance
proportional to velocity, one can write a differential equation like
mr''=-mgj - kr' which can be solved for r using an integrating factor
e^(kt/m).

The final solution for r, however, does not admit an interpretation for
k=0. Why is it that one does not get the ideal case to come from this
more general case when k=0?

I hope that the question makes sense.


Not to me. The assumption is unphysical, in my view.
Cd is proportional to V^2 ??
What am I missing, would you say?


Brian Whatcott
Altus OK Eureka!


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