# Capacitance

Capacitance is defined as the amount of charge stored in a capacitor per volt across the capacitor. The value of the capacitance is a measure of how rapidly a capacitor stores electric potential energy as the capacitor is getting charged up.

# Finding the Capacitance of a Parallel-Plate Capacitor

In this lesson, we'll prove that the capacitance of a parallel-plate capacitor does not depend on the charge or voltage of the capacitor but, rather, on only the size and geometry of the capacitor.

# Finding the Electric Field produced by a Parallel-Plate Capacitor

In this lesson, we'll determine the electric field generated by a charged plate. We'll show that a charged plate generates a constant electric field. Then, we'll find the electric field produced by two, parallel, charged plates (a parallel-plate capacitor). We'll show that the electric field in between the plates has a constant magnitude $$\frac{σ}{ε_0}$$. We'll also show that the direction of the electric field is a constant pointing from the positively charged plate to the negatively charged plate in a direction that is perpendicular to both plates. Lastly, we'll also prove that the electric field "outside" of the capacitor is zero everywhere.

# Calculating the amount of Electric Potential Energy Stored in a Capacitor

In this lesson, we'll determine the electric potential difference (also called voltage) across any arbitrary capacitor.