Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: A question on inelastic relativistic collisions



Hi Ed,
You wrote
----------


Imagine that there is a solid object at rest and in thermal
equilibrium
with a surrounding fluid. They are both at the same temperature.
Now a force
accelerates the solid object without without adding to its
internal
energy.

Is this in some way unreasonable. If not, the solid object
should have
the same temperature as before and the same temperature as the
fluid through
which it is now moving. But from the rest frame of the fluid would
not the
solid object now have a different average kinetic energy per
molecule?

Would there not now be a transfer of this molecular KE between
the solid
and the fluid -that is a transfer of heat between objects at the
same
temperature - in violation of the Second Law of Thermo?


Transfer of energy between two systems can occur
(1) because of a difference in temperature between the
systems (ands non-adiabatic walls between them) : heat
OR
(2) because of forces acting on the boundaries of the
systems: work
A transfer of energy through work between objects at the
same temperature is not a violation of the second law.
Brian McInnes