Magnetic permeability


 
(2003-07-26)     mo = 4p 10-7 N/A2 = 1.256637061435917295... mH/m

Magnetic permeability of the vacuum.  [Definition of the ampere (A)]

The relation   emc 2  =  1   and the exact value of c yield an exact SI value, with a finite decimal expansion, for Coulomb's constant:

 1      =     8.9875517873681764 ´ 10-9   »   9 ´ 10-9   N . m 2 / C 2
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Lisätietoa: Wikipedia