Re: N/kg versus m/s^2

["Prof. John P. Ertel (wizard)" <jpe@USNA.EDU>]

Now I really don't understand.  Units by there very definition cannot be
other than scalar.  Therefore, I don't understant the difference between
   "Newton DOT 1 meter"       and       "Newtons CROSS meters"
It simply makes no sense.  I hope we are not about to embark upon the
slippery ground that engineers tread where they distinguish between
   (meters)(newtons)       and        (newtons)(meters)
the former being units of torque and the latter being units or
work/energy.



On Fri, 26 Jan 2001, Zach Wolff wrote:

> > --- "Prof. John P. Ertel (wizard)" <jpe@USNA.EDU>
> > wrote:
> > (excerpt)
> > > After all, would we would never say (or would we?)
> > > that because the
> > > product of the force unit with the length unit is
> > > technically equivalent
> > > to the energy unit (Nm=J) that it would be OK to
> > > measure/quote the results
> > > of a calculation of torque in units of Joules.  Even
> > > if there is a unit
> > > equivalence here, it is at least misleading and I
> > > think just plain wrong!
> >
> > We would never calculate torque in terms of Joules
> > because 1 Joule = 1 Newton DOT 1 meter, whereas torque
> > is measured in units of Newtons CROSS meters.  This is
> > basic vector calculus.
> >
> > Zach Wolff
> >
> >
> >
> > __________________________________________________
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> > Yahoo! Auctions - Buy the things you want at great prices.
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