SI Units Stumper

[James.Langsted@rfets.gov (James Langsted)]

RADSAFE'rs:

The following question was printed in the "Wacky Questions" column of Denver's 
Rocky Mountain News, in a year-end column subtitled "Queries that stumped the 
staff."  In the column, Rebecca Jones (Miss-Becky@aol.com) and her staff 
research and answer all sorts of questions.

She's stumped on this one, and I am curious as well.  From previous postings, I 
know there's a group of units experts reading this.  Post your thoughts on the 
list and I'll forward them on to the columnist (with credit to you) or e-mail 
her directly.

Thanks
Jim Langsted, CHP
MH Chew & Associates
Golden, Colorado
73517.351@compuserve.com

"In the International System of Units, almost everything is defined in terms of 
something universally observable, like specific atomic wavelengths or 
frequencies.  There are two exceptions.  The kilogram is defined in terms of an 
artifact (which is, I believe, a platinum/iridium cylinder that resides in 
Paris).  The other is the mole, which is defined as the number of atoms in 12 
grams of carbon-12, and is thus derived from the kilogram.  It seems to me it 
would make more sense to just specify Avogadro's number once and for all, use it 
as the definition of the mole, and define the kilogram in terms of the mass of a 
mole of carbon-12.  Why doesn't it work this way? -- J-J Cote, Boulder"