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William Werner
11-07-2007, 12:48 PM
Sorry, I just don't agree with your first sentence. This is something
I have struggled with for a long time. Having individuals from
different disciplines with different degrees of expertise weighing in
on this "useless conversation" is exactly what I need to help me
understand that which I was much more insecure about just a few days
ago.

So, I may not have anything to add to the disagreement of what the
term should be, I definitely disagree with the statement that this is
a useless conversation. I learned from your comment, Dr. Robert
Soutas-Little, and from all the others.

Please, all, keep weighing in....for my sake.

Thanks,
Bill

**************************************
William Werner, PT, EdD
Supervisor of Rehabilitation and the Biomechanics Laboratory, Academic
Health Care Center of NYCOM
Associate Professor of Physical Therapy
New York Institute of Technology
Old Westbury, NY 11568
wwerner@nyit.edu
*****************************************

On 11/7/07, Robert Soutas-Little wrote:
> I have tried to resist weighing in on what is becoming a useless
> conversation. A moment is the turning effect of a force about a
> particular point in space and is defined by the vector equation r x F =
> M. The term moment is the preferred terminology for the turning effect
> of a force. The term torque is used interchangeably with moment in
> many applications, but is generally associated with twisting. This is
> particularly true is the study of elasticity or mechanics of deformable
> materials when torsion of shafts or Saint-Venant torsion theory and
> where moment is generally used when referring to bending of beams by
> transverse loading. ( See Elasticity; Robert Soutas-Little, Dover;,1999
> or Theory of Elasticity; Timoshenko and Gere). I could list dozens
> more references but to no point.
>
> People working in the general area of theoretical mechanics have a
> special obligation to people who are using their theories is such areas
> of biomechanics to be careful not to add confusion to the terminology.
> Something that I have learned after 55 years of research in both
> elasticity and biomechanics.
>
> I hope this is of some help in this discussion.
>
> Thanks,
> Robert Soutas-Little
> Professor Emeritus, Michigan State University
>
> On Wednesday, November 7, 2007, at 01:53 PM, Dr. Hamid Rassoulian
> wrote:
>
> > Hi again,
> >
> > Since I am tempted to make a more daring contribution would you
> > consider
> > having acquired a puncture whilst driving and you want to change the
> > wheel.
> > Also consider that you have at your disposal one of those general
> > purpose
> > spanners that look like a + with a socket at each end. So to take
> > off the
> > bolts of the wheel you would apply the spanner to the bolt and with
> > both
> > hands (one on either side, one pushing down and one pushing up) you
> > would
> > apply a "twisting" force or torque to the bolt. However, if you were
> > to use
> > one hand only you would be applying a turning moment to the bolt.
> >
> > thanks
> >
> > Hamid
> >
> >
> > --
> > Dr. H Rassoulian BSc, MSc, PhD, CEng, FIMechE
> > Clinical Scientist
> > Dept. Medical Physics & Bioengineering
> > Southampton General Hospital
> > Tremona Rd.
> > Southampton SO16 6YD
> >
> > Tel: +44 (0)23 80 79 69 45
> > Fax: +44 (0)23 80 79 41 17
> > Alternative Email:
> > Hamid.Rassoulian@suht.swest.nhs.uk
> >
> >
> > =================================================
> > PLEASE DO NOT PRINT UNLESS ON Recycled unbleached paper
> > =================================================
> >
> >
> >
> >
> >
> > Quoting Dale Cannavan :
> >
> >> Dear Subscribers,
> >>
> >>
> >>
> >> Can anyone explain / define the differences in the meaning of Torque
> >> and
> >> Moment. It is often stated that they are synonymous; however, some
> >> suggest they are different.
> >>
> >>
> >>
> >> Thanks for your time,
> >>
> >>
> >>
> >> Dale Cannavan
> >>
> >> Ph.D. Candidate
> >>
> >> Centre for Sports Medicine and Human Performance
> >>
> >> Department of Sports Sciences
> >>
> >> Brunel University
> >>
> >> West London
> >>
> >>
> >>
> >>
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> >>
> >>
> >>
> >>
> >
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> > ---------------------------------------------------------------
> >
> Robert Soutas-Little PhD
> Professor Emeritus of Engineering Mechanics
> Michigan State University
> P.O. Box 1143
> Leland, Mi 49654
> Tel: (231) 256-7646 FAX: (231) 256-7708
>
> FedEx and UPS address:
> 187 S. Highland Dr.
> Lake Leelanau, MI 49653
>
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