Field and Wave Electromagnetics 2nd Edition by David Cheng

Exercise 10

The radius of the core and the inner radius of the outer conductor of a very long coaxial transmission line are r i and r 0 , respectively. The space between the conductors is filled with two coaxial layers of dielectrics. The dielectric constants of the dielectrics are r 1 for r i r b and r 2 for b r r 0. Determine its capacitance per unit length.