Siemens(redirected from Ernst von Siemens)
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the unit of electrical conductivity in the International System of Units (SI). Named in honor of W. von Siemens, the unit has the designation S in the international system. A Siemens is equal to the electrical conductivity of a conductor having a resistance of 1 ohm. In the 19th century, the Siemens was a unit of electrical resistance. Now obsolete, it was equal to the resistance of a column of mercury with a length of 1 m and a cross-sectional area of 1 mm2 at 0°C.