Units used with the SI, and whose values in SI are obtained experimentally
The unified atomic mass unit is 1/12 of the mass of an atom of the nuclide 12C.
The electronvolt is the kinetic energy acquired by an electron passing through a potential difference of 1 volt in a vacuum.
Quantity
|
Unit
|
|
|
|
Name
|
Symbol
|
Value
|
Mass
|
unified atomic mass unit
|
U
|
1 u » 1,6605655 x 10-27 kg
|
Energy
|
electronvolt
|
eV
|
1eV » 1,6021892 x 10-19 J
|
The value of these units, expressed in SI units, is not known exactly.
The prefixes and their symbols listed in
F-II, Annex 2,
1.3 may be used in conjunction with these two units and with their symbols.