Re: [Phys-l] pseudo-force

[Jack Uretsky <jlu@hep.anl.gov>]

Hi Anthony-
	In the reference frame of the car, the passenger feels pushed 
toward the outside of the turn.  The force is "pseudo" because it is only 
defined in an accelerated reference frame.  It is easily demonstrated by 
hanging a pendulum from the roof of the car.  The pendulum also reports 
pseudo-forces from linear accelerations.  This is hard to get across?
						Regards,
							Jack


On Thu, 26 Oct 2006, Anthony Lapinski wrote:

> Pseudo forces are usually mentioned during circular motion. Everyone knows
> that when you turn your car sharply to the right, you move to the left. So
> you naturally think there is an outward "centrifugal" force on you. But
> it's really just your inertia -- your tendency to want to move in a
> straight line. There isn't an outward force (on you) because every force
> must have a source! So we call these outward forces "pseudo forces." There
> IS an outward force, but it does not act on the object in question  .It's
> just the reaction force of the net inward (centripetal) force for an
> object moving in a circle. Or spin a stopper. The inward (net) force is
> the string on the stopper. The reaction force is the stopper on the
> string. It is outward, but does NOT act on the stopper (as many people
> believe).
>
> This is a very difficult concept for my students, and for most people.
>
> Hope this helps!
>
> Forum for Physics Educators <phys-l@carnot.physics.buffalo.edu> writes:
> > Some questions:
> >
> >  What do people mean by the term "pseudo-force"?
> >
> >  Is a pseudo-force a force?
> >
> >  Why is it called a pseudo-force?
> >
> >  Is this concept crucial/useful/marginal/unhelpful?
> >
> > _______________________________________________
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> > https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
>
>
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