Pre-Quantum Electrodynamics

Fundamentals: After properly studying this module, you should be able to:

• state what the polarization of an object is
• give the relationship between polarization and surface/volume bound charges
• explain the concept of free charge
• state the definition of the electric displacement
• state Gauss's law relating displacement and free charge density (in both differential and integral form)
• explain what a linear dielectric is
• explain what the electric susceptibility, permittivity and dielectric constant of a material are

Applications: As a strict minimum, you should be able to:

• using Gauss's law, derive the displacement for all basic geometries (sphere, plate capacitor, wire with dielectric cladding)
• derive boundary conditions for the displacement
• calculate the change in capacitance of a parallel plate capacitor filled with dielectric (as compared to one filled with vacuum)
• derive boundary conditions for fields or potentials at the interface between two dielectrics