physical constants

*To*: mathgroup at smc.vnet.net*Subject*: [mg82018] physical constants*From*: "Chris Chiasson" <chris at chiasson.name>*Date*: Tue, 9 Oct 2007 05:44:35 -0400 (EDT)

ElectronCharge has the wrong sign. ElementaryCharge, if it existed, should have the sign that ElectronCharge currently has. In[1]:= << PhysicalConstants` ElectronCharge Out[2]= 1.60218*10^-19 Coulomb Also, to continue beating a dead horse from a couple of years ago: VacuumPermittivity is incorrectly defined as a machine precision float. VacuumPermittivity should be defined as an exact transcendental number. The following links and code make this clear: http://physics.nist.gov/cgi-bin/cuu/Value?eqep0 http://physics.nist.gov/cgi-bin/cuu/Value?eqmu0 http://physics.nist.gov/cgi-bin/cuu/Value?c In[3]:= VacuumPermittivity Out[3]= (8.85419*10^-12 Ampere Second)/(Meter Volt) In[5]:= (1/(VacuumPermeability*SpeedOfLight^2)) % // N Out[5]= (625000 Ampere Second)/(22468879468420441 Meter \[Pi] Volt) Out[6]= (8.85419*10^-12 Ampere Second)/(Meter Volt) -- http://chris.chiasson.name/