1. The problem statement, all variables and given/known data Hi. I want to calculate electric field radiated by 50 Hz transmission line (overhead power line). for this I'm thinking about Gauss law which can help. in this case I have formula E = lambda / 2*pi*eps0*r where lambda is charge per unit length (unit: Coloumb / m). the problem is that if I want to calculate electric field E, how I can get value for lambda ?... is there another formula for lambda ?