Value of Vacuum Permittivity/Proof 2

Proof
The vacuum permittivity is the physical constant denoted $\varepsilon_0$ defined as:


 * $\varepsilon_0 := \dfrac 1 {\mu_0 c^2}$

where:
 * $\mu_0$ is the vacuum permeability defined in $\mathrm H \, \mathrm m^{-1}$ (henries per metre)
 * $c$ is the speed of light defined in $\mathrm m \, \mathrm s^{-1}$

$\mu_0$ has the value determined experimentally as:
 * $\mu_0 \approx 1 \cdotp 25663 \, 70621 \, 2 (19) \times 10^{-6} \, \mathrm H \, \mathrm m^{-1}$

$c$ is defined precisely as:
 * $c = 299 \, 792 \, 458 \, \mathrm m \, \mathrm s^{-1}$

Hence $\varepsilon_0$ can be calculated as: