Hi, once again i need help with electromagnetics. :grumpy: if anyone can help, it would be greatly appreciated. here is teh problem: 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(o), respectively. The space between the conductors is filled with two coaxial layers of dielectrics. The dielectric constants of the dielectrics are Epsilon(1) for r(i)<r<b. and Epsilon(2) for b<r<r(o). Determine it's capacitance per unit length. From what i already know, the Capacitance=Q/V. So in order to find Q and V, we have to find the integral of Q and V? CAn someone point me to the right direction? I'm so lost in electromagnetics, i don't even know which equations to use.