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Re: centrifugal force



Why do you say the agent has that property? Does the property have
to pertain to the agent? How does one make that decision? Isn't it
more natural to ascribe that property to the force itself? That is
what is usually done, as it is in the statement of the principle
of equivalence in terms of forces. Alternatively it is a property
of the mass itself, the principle of equivalence being stated in
that case by saying that gravitational and inertial masses are
equal.

Leigh


I'm probably getting tied up in the language used....

The introduction of a "non-intertial" force to explain the trajectories of
objects when observed from a non-inertial reference frame is a way of
preserving Newton's laws. This introduced force must have the property of
the force being proportional to the mass (as gravitational force does):
otherwise the trajectory would be different than when observed from an
inertial frame.

Interactive Physics is a useful tool here: John Mallinckrodt has developed
some excellent simulations which show this. (Thanks John!) The path of the
diver in the rotating space station is the same regardless of the mass of
the diver (who is after all just moving in a straight line...).

The properties of the non-inertial forces are best described as properties
of the non-inertial frame, rather than the objects or the "agents" of the
force.

Paul


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Paul Yates
Department of Physics
University of Otago
PO Box 56 Fax: (64)3 479 0964
Dunedin Phone: (64)3 479 7742
New Zealand Cell: (025) 412 202
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~