> From: Ian Mills <[EMAIL PROTECTED]>
note: Mr. Mills is president of the CCU of the BIPM
> Forwarded by: Gene Mechtly <[EMAIL PROTECTED]>
> Subject: [USMA:13340] Re: Symbols for SI Prefixes (fwd)
>
> We (CCU) decided that both "SI units" and "Units of the SI" should be names
that
> covered the whole lot, and that when one wishes to
> refer to only the base and derived units without prefixes one should use the
> name "coherent SI units".
Hooray!
I've been hoping for some sort of resolution to this problem for some time.
I first encountered it as a problem when I proposed that the publications of
the American Association of Physics Teachers require that all measurements
referred to in their publications should "be in SI units". I was not yet
well versed in the details of SI and did not realize then that, technically,
"SI units" meant ONLY the basic unists of each kind of measurement,
generally those without prefixes (except the basic unit of mass which is the
kilogram and not the gram).
If my suggestion had been adopted as proposed, it would have prohibited the
use of millimetres, kilowatts, milligrams (and even grams), and all the
other prefixed units. That was not what I had intended. The proposal
eventually was changed to say "units of the SI system" (or just "units of
the SI", the word system being redundant) and was ultimately implemented
with some exceptions.
The new proposal, if finally adopted*, would allow us to say just "SI units"
when we mean ANY of the units included in the SI system, whether they be
prefixed or not.
Regards,
Bill Hooper
* TO Gene Mechtly:
A proposal by the CCU (Consultative Committe on Units, I think) must still
be approved by one or more other bodies (CGPM and/or BIPM), does it not?
============
Keep It Simple!
Make It Metric!
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