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RE: Propellant fluid dynamics at zero-g

> > ... though I hate the term centrifugal force... but anyway . . .
> My wife (teaches physics) insists on the "centripital force" 
> (which is the
> correct term for the restraining "force"), but it just don't convey
> the meaning of things "flying" outward.

Centripetal force is a real force.  it is the force that pulls an object in
a curved path towards the centre of the curve.  For example, if you swing a
rock in a circle over your head, the centripetal force is provided by the
string (unless it breaks! :) ).  With a satellite, the force is provided by
gravity.  With a spinning satellite, centripetal force comes from the
satellit's own frame (that's what stops it flying apart when it spins!).

Centrifugal force isn't a real force, but a "reaction force" caused by the
inwards acceleration of the centripetal force.  Much like weight is caused
by the reaction of the ground against our bodies which are being pulled into
the Earth by gravity...

> So in a compromise to save our marriage, I now only use the term
> "centrifugal effect"...  and have achieved peace in the household...

Hehe, cute. :-)
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