\section{Capacitance, Dielectrics, and Energy Storage}

This unit shifts the focus from electric fields and potentials produced by isolated charge distributions to systems designed to store electric energy: capacitors. The central idea is that a conductor (or pair of conductors) can hold charge and associated electric potential energy in a controlled geometry, and that the ability to store charge at a given voltage is quantified by the capacitance $C$.

The flow begins with conductors in electrostatic equilibrium, where charge resides entirely on surfaces and the interior field vanishes. It then covers charge redistribution through contact, induction, and grounding. Next, capacitance and the standard capacitor geometries (parallel-plate, spherical, cylindrical) are introduced, followed by the energy stored in capacitor electric fields. The unit concludes with dielectrics, showing how inserting an insulating material increases capacitance through polarization.

\input{concepts/em/u10/e10-1-conductors.tex}

\input{concepts/em/u10/e10-2-charge-redistribution.tex}

\input{concepts/em/u10/e10-3-capacitance.tex}

\input{concepts/em/u10/e10-4-capacitor-energy.tex}

\input{concepts/em/u10/e10-5-dielectrics.tex}
