Re: Free body diagram

[Leigh Palmer <palmer@sfu.ca>]

>     I fail Acompanying text:to see the  following free body diagram.  The
> Physics Teacher Vol. 31, Feb. 1993 ;  diagram #27. Accompanying text:
> Small stone resting against the frictionless  inside wall of a cone
> rotating about its vertical axis at constant speed.   Not accelerating
> vertically.  Moving straight out of the  paper.     For those of you who
> cannot  access the article, the cone's apex is down.   My question: Does
> it matter wether it  is the cone or the stone that is rotating? Please
> help with the  FBD.

Rotation of a circular cone is irrelevant if it is hypothetically
frictionless and rotating about is symmetry axis. Forces exerted
on the stone will depend upon many geometrical factors as well as
on its rotational speed, but it is interesting to note that the
component of the stone's angular momentum parallel to the cone's
axis is an invariant of the motion.

I'm sorry, I can't get to that Physics Teacher just now.

Leigh