Permittivity of a vacuum

The insulating property of any insulator will break down in a sufficiently strong electric field. The dielectric strength is defined as the electric strength (V/m) which an insulating material can withstand. For plastics the dielectric strength can vary from 1 to 1000 MV/m. Materials may be compared on the basis of their relative permittivity (or dielectric constant). This is the ratio of the permittivity of the material to the permittivity of a vacuum. The ability of a... 

Electron mass, m Permittivity of a vacuum, eo Speed of light in a vacuum, c Gas constant, R... 

An atomic unit of length used in quantum mechanical calculations of electronic wavefunctions. It is symbolized by o and is equivalent to the Bohr radius, the radius of the smallest orbit of the least energetic electron in a Bohr hydrogen atom. The bohr is equal to where a is the fine-structure constant, n is the ratio of the circumference of a circle to its diameter, and is the Rydberg constant. The parameter a includes h, as well as the electron s rest mass and elementary charge, and the permittivity of a vacuum. One bohr equals 5.29177249 x 10 meter (or, about 0.529 angstroms). 

The fifth letter in the Greek alphabet hence, used to denote the fifth in a series (for example, the fifth methylene carbon in a fatty acid). 2. Symbol for molar absorption coefficient or extinction coefficient. 3. Symbol for permittivity (cq refers to permittivity of a vacuum refers to relative permittivity). 4. s, Symbol for degree of activation (lUB (1982) Eur. J. Biochem. 128, 281). 5. 8i, Symbol for degree of inhibition. 6. Symbol for efficiency. 7. Symbol for linear strain. 8. Symbol for emit-tance. 

The permittivity of a material is the constant e in the rationalised expression, F = (0i02)/(47rer2), where F is the force between charges Q and 02 separated by a distance r. The permittivity of a vacuum <6 according to this definition is equal to 8.854 x 1012 kg m 3 s4 A2. The dielectric constant of a material is equal to the ratio between its permittivity and the permittivity of a vacuum, and is a dimensionless quantity. 

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