It is the well known constant, called as dielectric constant. It is the permittivity in a vacuum.
It is equal to 8.854187817620 x 10^(-12) Fards per meter (Fm^(-1))
it is a quantity measuring the ability of a substance to store electrical energy in electric field..
vaccume permittivity is an ideal, physical content, which is the value of the deelectric permittivity of classical vaccume.
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