Electric Constant

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electric constant

[i¦lek·trik ′kän·stənt]
The permittivity of empty space, equal to 1 in centimeter-gram-second electrostatic units and to 107/4π c 2 farads per meter or, numerically, to 8.854 × 10-12 farad per meter in International System units, where c is the speed of light in meters per second. Symbolized ε0.

Electric Constant


(or permittivity of free, or empty, space), the constant of proportionality ∊0 in Coulomb’s law, which gives the force of interaction between two point charges at rest.

In the International System of Units (SI), ∊0 = 10 7/4πC 2 farads per meter (F/m) = 8.85418782 ± 0.00000007 F/m, where c is the speed of light in m/sec. In the centimeter-gram-second (cgs) electrostatic system and in the Gaussian system, ∊0 is taken to be a dimensionless factor equal to unity.

In contrast to the dielectric constant ∊, which depends on the type of substance, temperature, pressure, and other parameters, the electric constant ∊0 depends only on the choice of a system of units.

References in periodicals archive ?
Thus, the electric constant s0 makes sense the linear density of the vortex tube current, and the magnetic constant [[mu].
In Japan and Russia, scientists are levitating masses with superconductors; in Germany, experimenters are debugging a vacuum Faraday system, whereby gold atoms beamed onto a collector yield an electric constant, from which an Avogadro number can be derived.
The main standard quantum number can be expressed through the mass M of the contour and its density per one meter (the electric constant [[epsilon].