申論題

2.(10%) For a coaxial transmission line, Fig. 1, the capacitance per unit length is , and the inductance per unit length is. At high frequencies, the internal inductance drops  off. Find the characteristic impedance of the coaxial line, , at high frequencies. Please also write down the unit of Zo, i.e,, what is the square root of (H/F)? What is the speed the wave travels in the coaxial cable? You can find it by calculating velocity = .