Re: vertical fall

[John Mallinckrodt <ajmallinckro@CSUPomona.Edu>]

On Sat, 1 Nov 1997, LUDWIK KOWALSKI wrote:

> A spherical object is moving vertically down through a medium, such as air 
> or water. Its potential energy decreases. Initially a large fraction of PE
> is converted into KE but but eventually this conversion process stops (at
> the macroscopic level) and PE is converted into Q. The law of conservation 
> of energy would not be violated if a fraction of the translational KE were 
> converted into rotational energy. But that macroscopic conversion does not
> happen (?). A "degree of freedom" is available but the energy does not go
> into it. Why? Which law is responsible for this?

Why do you say that energy doesn't go into it?  On the other hand, do you
actually expect to be able to observe it?  After all, in the absence of
any organized forcing mechanism, this "degree of freedom" would be
expected to end up with an energy of less than 10^(-20) J just like all
the others.  I certainly wouldn't expect it to figure prominently in the
solution. 

John
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