See the mechanics text by Barger and Olson, section 6-13 in my edition.
Friction at the table interface provides the required torque, as I
remember.
Bob Sciamanda (W3NLV)
Physics, Edinboro Univ of PA (em)
trebor@velocity.net http://www.velocity.net/~trebor
----- Original Message -----
From: "Ron Curtin" <curtin@CCDS.CHARLOTTE.NC.US>
To: <PHYS-L@lists.nau.edu>
Sent: Monday, May 06, 2002 12:47 PM
Subject: Spinning Class Ring
| A student asked me a question that I have heard before, but I don't know
a
| good answer. If you spin a class ring on a table top, it spins around
so
| that the heavy part (the front of the ring) always moves up to a
position
| furthest above the tabletop. It doesn't matter if the heavy part of the
| ring starts at the bottom or at the top. The student and I wonder why
this
| happens.
|