I’m trying to determine the how close 2 parallel infinitely long cylindrical conductors can get before they will arc together. Assume the conductors will be separated only by air, and I know that the Dielectric Strength of air is 3x10^6 V/m. So I figured that if I can come up with a formula to determine the E field I can find where the E field = the dielectric strength of air which should be the point at which they will begin to arc. Assuming the following... I have two parallel conductors with radius r, separated by distance d. Each conductor is carrying a time varying (AC) current I at 60 hz. The currents are flowing in opposite directions. The conductors also have a time varying (AC) voltage of V, but I don’t think this matters for determining E field magnitude. What I hope to come up with is a formula for the magnitude of E in terms of r, d, I, and V. Can anyone please help with the formula for E. P.s. This is not a homework question but if it would be moer apprpriate for that section I could post it there.