Coax Impedance:
In class, we derived the electric and magnetic fields
in a coaxial transmission line.
From those we deduced the characteristic impedance of a coaxial cable:
where a is the radius of the inner coax line
and b is the radius of the outer coax cylinder, as shown.
In general, the characteristic impedance of a
transmission line is given by
where
and
are the inductance and capacitance
per unit length, respectively.
Show that the characteristic impedance of this
coax line satisfies this definition by calculating
and
explicitly, and then Z.