> Philip.Belben_at_pgen.com wrote:
> > Metre, Kilogram, Second, Ampere, Kelvin, Mole and Candela (normally
> Kilogram? Why not gram?
Since the base unit is the Kilogram. As Philip said,
the Mass is still defined by the artefact kilogram
in Paris - there is no other definition until now.
BTW: Tey are about to replace the 'first' Kilogram
by a new model, made from a single Silicon cristal.
Since, if the process of 'building' a prototype
Kilogram artefact can be better defined, a higher
accuracy can be reached. This is part of the
international Avogadro project to redefine the
Kilogram via a non prototype artefact method.
For example, within a cristal the number of Si
atoms can be determinated - now the kg (or g)
can be based on the Mole (via the definition of
usin Si and a fixed number).
Gruss
H.
--
Ich denke, also bin ich, also gut
HRK
Received on Fri Jan 22 1999 - 13:34:30 GMT