Siemens (unit)
The siemens (symbol: S) is an SI derived unit of measurement for electric conductance, being the inverse of the ohm (Ω), named after Werner von Siemens.
<math>S = A/V<math>
- S = Siemens
- A = Amperes
- V = Volts
- The forumla for computing conductance is as follows:
- G = Conductance
- R = Resistance (Ω)
- S = Siemens
Example: G = 1 / 6 Ω = 0.1667 S
Mho is a now eccentric name for this unit of electrical conductance, equal to 1 Ω−1. It is derived by spelling ohm backwards. Its symbol is <math>\mho<math> (the upside-down letter Ω). The term siemens is used universally in science and primarily in electrical applications, while mho is used primarily in electronic applications.
SI electricity units
| SI electromagnetism units | |||
|---|---|---|---|
| Name | Symbol | Dimensions | Quantity |
| ampere (SI base unit) | A | A | Current |
| coulomb | C | A·s | Electric charge, Quantity of electricity |
| volt | V | J/C = kg·m2·s−3·A−1 | Potential difference |
| ohm | Ω | V/A = kg·m2·s−3·A−2 | Resistance, Impedance, Reactance |
| ohm metre | Ω·m | kg·m3·s−3·A−2 | Resistivity |
| farad | F | C/V = kg−1·m−2·A2·s4 | Capacitance |
| farad per metre | F/m | kg−1·m−3·A2·s4 | Permittivity |
| reciprocal farad | F−1 | kg1·m2·A−2·s−4 | Elastance |
| siemens | S | Ω−1 = kg−1·m−2·s3·A2 | Conductance, Admittance, Susceptance |
| siemens per metre | S/m | kg−1·m−3·s3·A2 | Conductivity |
| weber | Wb | V·s = kg·m2·s−2·A−1 | Magnetic flux |
| tesla | T | Wb/m2 = kg·s−2·A−1 | Magnetic flux density |
| ampere per metre | A/m | m−1·A | magnetic induction |
| ampere-turns per weber | A/Wb | kg−1·m−2·s2·A2 | Reluctance |
| henry | H | V·s/A = kg·m2·s−2·A−2 | Inductance |
| henry per metre | H/m | kg·m·s−2·A−2 | Permeability |
| (dimensionless) | - | - | Magnetic susceptibility |
Categories: SI derived units | Units of electrical conductance