The convention arises from mathematics, Bill. Torque is defined as a
cross product. Using T for torque (normally tau is used) and X for the
cross-product operator,
T = r X F
Necessary to this is the convention that radius points outward from the
center of action. Also, mathematics establishes the direction of a cross
product such that if one were to cross the x-axis unit vector into the
y-axis unit vector, the z-axis unit vector results. This defines our
"right-hand coordinate system" which is based on the "right-hand rule",
again, a mathematics convention.
One can write this in a nifty manner using matrices but I don't feel
like messing with it here and I suppose very few here would really care
to see it! Those that do can consult any introductory calculus text or
physics text. ;-)
I have never learned of nor have I seen any definition for the
reciprocal of a vector, by the way, but I'm not a mathematician.
Jim
Bill Potts wrote:
>
> Nat Hager wrote:
> > It's a convenient formalism used in rotational mechanics.
>
> For those of us who are not practitioners of rotational mechanics, it's a
> somewhat inconvenient formalism, as it violates the usual mathematical
> definition of vector.
>
> However, thanks for adding to my relatively limited knowledge of that field.
> <g>
>
> Bill Potts, CMS
> San Jose, CA
> http://metric1.org [SI Navigator]
--
Metric Methods(SM) "Don't be late to metricate!"
James R. Frysinger, CAMS http://www.metricmethods.com/
10 Captiva Row e-mail: [EMAIL PROTECTED]
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