http://www.kabculus.com/capacitance-and-inductance-matrices/node7.html this short page describes conductor bundles, which are power transmission lines hung paralell to eachother. i think the page is trying to explain why, when they are hung that way that they reduce impedance per meter, but i dont get it. i understand all the variables they are using except what it is they are calculating. r is an approximation for the radius of the conductors' cross section (i think) R is how far away the cables are hung from the center of the bundle (i think) e0 is the permeability of free space potential? that means voltage right? why are they using the greek letter for angle? why isnt it 120v rms? and what is a2 and a4? equivalent radius?