Definition, with examples of capacitance for spheres and for parallel plate capacitors.

How to make a small parallel plate capacitor with a large capacitance. Finding the amount of energy stored in a parallel plate capacitor.

Starting to charge a large capacitor to a potential difference of 3000 V.

Explanation of the concepts behind a camera flash, with a demonstration using several capacitors and a light bulb.

Examples of Professor Edgerton's high speed photography, including images of a bullet fired through a light bulb and a balloon being popped. Brief discussion of strobe lights and their uses.

After 15 minutes of charging, the capacitor is quickly discharged over a fuse with impressive results.

Exploring work required to separate two oppositely charged parallel plates, with definition of field energy density and potential energy stored in an electric field.

Using an actual parallel plate capacitor to show that positive work must be done to increase the distance between the two plates.

The effects of increasing the separation between the plates of a capacitor.

The effects of increasing the separation between the plates of a capacitor that is still connected to a power supply.

Effects of area, separation distance, and dielectric constant on the capacitance of a parallel plate capacitor.

Definition and demonstration of a Leyden Jar.

Finding the electric field, potential difference, capacitance, and electrostatic potential energy of a parallel plate capacitor.

Demonstration of the Leyden Jar, with explanation of the physics behind the unexpected result.

Definition, with example of parallel-plate capacitor. Link to visualization; calculation of E, delta V, and C for parallel-plate capacitor and for spherical capacitor. Capacitance of Earth; 1 Farad is very large.

Step-by-step calculation of work done to charge a parallel-plate capacitor. Energy in a capacitor is stored in the electric field. Example of energy in a 1 Farad capacitor.

Energy stored in electric and magnetic fields, as well as in capacitors and inductors. The Poynting vector and intensity of electromagnetic radiation.

Definitions, with diagrams and equations. Equations for energy stored in a capacitor.

Finding the equivalent capacitance of capacitors in series and in parallel, with equations and diagrams.

Capacitance and units; definition of capacitor; capacitance of sphere, parallel-plate, spherical, cylindrical capacitors.

Leyden jars and Wimshurst machine; dielectrics; energy stored by E-field in capacitor.

Capacitance in series and in parallel; applications and problems.

Definition and uses; calculation for parallel-plate, spherical, and cylindrical capacitors.

Calculation of stored energy; energy density of electric field with examples.

Strategy for capacitance calculation; equivalent capacitance, capacitor with two dielectrics, capacitor on a spring.

Three questions about changing the dimensions of a parallel plate capacitor, with answers and explanations.

4-part capacitor problem; finding voltages across capacitors for different switch configurations.

Solution (PDF)

Calculating current, charge, capacitance delivered to Van de Graaff generator.

Solution (PDF)

5-part problem; finding V, stored energy, work to move plates; inserting dielectric.

Solution (PDF)^#

Comparison of capacitors; showing that with narrow gaps, these capacitors can be approximated as parallel-plate capacitors.

Solution (PDF)

4-part problem; finding voltage, stored energy; explaining conservation of energy in different cases.

Solution (PDF)^#

Force on electron; balancing electric and magnetic forces.

Solution (PDF)

Showing that an electric field does not abruptly drop to 0 at capacitor edge.

Solution (PDF)

5-part problem; finding charge, potential energy, and electric potential.

Solution (PDF)^#

4-part problem; finding E-field, trajectories for particle; computing kinetic energy.

Determining energy stored in parallel-plate capacitor with and without dielectric.

Solution (PDF)^#

Applet simulating the behavior of the charges inside the plates of a parallel plate capacitor.

Applet simulating the behavior of a conducting sphere placed between the plates of a parallel plate capacitor as it is being charged.