Calculation of electric fields due to lines of charge

The amplitude of the electric field due to a straight line segment of uniform electric charges is shown to be given by E=2q (4πDε₀)^-1 sen (α/2) where q is the linear charge density, α is the viewing angle (from the observation point to the filament extremities), and D is the distance to the filament; furthermore, the direction of the vector E lies on the bisector of the viewing angle. This result can greatly reduce the computation time in the analysis of EMC (electromagnetic compatibility) problems involving static or quasi-static charge distributions