Definition:Impedance of Free Space/Dimension

Definition

The impedance of free space has the dimension $\mathsf {M L^2 T^{-3} I^{-2} }$.

This arises from its definition as:

electric field strength per unit magnetic field strength:

$\dfrac {\mathsf {M L T^{-3} I^{-1} } } {\mathsf {I L^{-1} } }$

vacuum permeability multiplied by the speed of light:

$\mathsf {M L T^{-2} I^{-2} } \times \mathsf {L T^{-1} }$

the square root of the quotient of the vacuum permeability by the vacuum permittivity:

$\sqrt {\dfrac {\mathsf {M L T^{-2} I^{-2} } } {\mathsf {M^{-1} L^{-3} T^4 I^2} } } = \sqrt {\mathsf {M^2 L^4 T^{-6} I^{-4} } }$