Transmission Line Basics

Field Quantities

E: Electrical field intensity (V/m).; Defined as the electric force on a unit charge. Only vector needed in discussing electrostatics (effects of stationary electric charge) in free space.
D: Electric flux density or electric displacement (C/m2).; Useful in the study of electric field in material media.
B: Magnetic flux density (T, Tesla, V-sec/m2).; Magnetic force acting on a charge moving with a given velocity. Only vector is needed in discussing magneto statics (effects of steady electric currents) in free space.
H: Magnetic field intensity (A/m).; Useful in the study of magnetic field in material media.

c = \frac{1}{\sqrt{ε_{0} μ_{0}}} m/s

Or,

ε_{0} = 1 / (c^{2} μ_{0})

\approx {(1 / 36 π)}^{'} 10^{- 9} F/m

Where,

$c$: Velocity of electromagnetic wave (including light).; $c \approx 3^{'} 10^{8} m/s$
$ε_{0}$: Permittivity of free space.; $D = ε_{0} E$
$μ_{0}$: Permeability of free space.; $H = (1 / μ_{0}) B, μ_{0} = 4 π^{'} 10^{- 7} H/m$

$ε_{0}$ and $μ_{0}$ are not independent.