Educator

Application of Gauss's Law, Part 2

• Gauss’s law may be used to determine the electric field E produced by charge distributions with high symmetry.
• For an infinitely long line of charge with charge density lambda C/m, the electric field at a distance r from the line is E = lambda /(2*pi*epsilon_0*r), and is radial.
• For an infinite sheet of charge with density sigma C/m^2, E = sigma / (2*epsilon_).
• Between the plates of a parallel plate capacitor, E = sigma / epsilon_0. Outside, E = 0.
• For a conductor in electrostatic equilibrium, the electric field is zero everywhere inside the conductor. Also, any excess charge added to the conductor will reside on the surface of the conductor. At a point on the surface of the conductor, E = sigma / epsilon_0, where sigma is the surface charge density on the conductor.