1. The problem statement, all variables and given/known data We need to connect two coax cables with the same dielectric (εr = 9) but with different dimensions as shown. How big must be the radius of the outer conductor of the second line in order to match two lines? How would the velocity of the wave propagation change, if we remove the dielectric? What’s about the characteristic impedance? 2. Relevant equations Zc=sqrt(μ/ε)((ln(b/a))/(2∏)) μ=μrμ0 ε=εrε0 3. The attempt at a solution I so far have uploaded my answer to the radius part am I right? For the last conceptual parts I am not sure and need a bit of help.