permittivity of vacuum

https://dx.doi.org/10.1351/goldbook.P04508
Fundamental physical constant ɛ 0 = 1 μ 0 c 0 2 exactly, where μ 0 is the permeability of vacuum and c 0 the speed of light in vacuum. It is equal to 8.854 187 817 ... × 10 −12 F m −1.
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