Electrostatic Energy: Charge Distribution and Dielectrics

This lecture covers the concept of electrostatic potential energy, starting with the work required to assemble a charge distribution in a vacuum. It then explores the energy density, divergence theorem, and the total potential energy of charges in an electric field. The discussion extends to the interpretation of potential energy when dielectrics are involved, distinguishing between linear and nonlinear systems. Various examples are provided, including the electrostatic energy of two charges, an insulating sphere with different permittivities, and a distribution of charges on a conductive sphere.