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Re: [Phys-l] Coriolis effect puzzlement



On 12/07/2011 11:21 AM, Bernard Cleyet wrote:

I'm confused here. I thought there were two effects. Energy
conversion due to tidal absorption that results in object separation,
and rotation period change. Is the latter also due to energy
absorption, or is it possible with a rigid asymmetrical satellite?

Well, to make the process work, *either* the earth or the
moon has to be dissipative.

Previously I said balls roll downhill. Hypothetically, in
the complete absence of dissipation, the ball would roll back
up the other side and would never settle at the bottom.


I am reminded of the immortal words of David Goodstein. In the book
_States of Matter_ the section on “Variational Principles in
Thermodynamics” begins by saying:

Fundamentally there is only one variational principle in thermodynamics.

The fundamental principle is nondecrease of the entropy of the
entire situation. Other variational principles (such as balls
rolling downhill) must be considered rather weak corollaries of
this one great principle.

Minimization of energy, or free energy, or free enthalpy of the
system is fine, under suitable restrictions, but in every case
that is just a proxy for maximization of entropy of the system
plus surroundings.
http://www.av8n.com/physics/spontaneous.htm

Remember:

Fundamentally there is only one variational principle in thermodynamics.