Electricity and Magnetism

Balloons and Static Electricity

Why does a balloon stick to your sweater? Rub a balloon on a sweater, then let go of the balloon and it flies over and sticks to the sweater. View the charges in the sweater, balloons, and the wall.

John Travoltage

Make sparks fly with John Travoltage. Wiggle Johnnie's foot and he picks up charges from the carpet. Bring his hand close to the door knob and get rid of the excess charge.

Electric Field of Dreams

Play ball! Add charges to the Field of Dreams and see how they react to the electric field. Turn on a background electric field and adjust the direction and magnitude. (Kevin Costner not included).

Charges and Fields

Move point charges around on the playing field and then view the electric field, voltages, equipotential lines, and more. It's colorful, it's dynamic, it's free.

Electric Field Hockey

Play hockey with electric charges. Place charges on the ice, then hit start to try to get the puck in the goal. View the electric field. Trace the puck's motion. Make the game harder by placing walls in front of the goal. This is a clone of the popular simulation of the same name marketed by Physics Academic Software and written by Prof. Ruth Chabay of the Dept of Physics at North Carolina State University.

Battery Voltage

Look inside a battery to see how it works. Select the battery voltage and little stick figures move charges from one end of the battery to the other. A voltmeter tells you the resulting battery voltage.

Battery Resistor Circuit

Look inside a resistor to see how it works. Increase the battery voltage to make more electrons flow though the resistor. Increase the resistance to block the flow of electrons. Watch the current and resistor temperature change.

Resistance in a Wire

Learn about the physics of resistance in a wire. Change its resistivity, length, and area to see how they affect the wire's resistance. The sizes of the symbols in the equation change along with the diagram of a wire.

Ohm's Law

See how the equation form of Ohm's law relates to a simple circuit. Adjust the voltage and resistance, and see the current change according to Ohm's law. The sizes of the symbols in the equation change to match the circuit diagram.

Signal Circuit

Why do the lights turn on in a room as soon as you flip a switch? Flip the switch and electrons slowly creep along a wire. The light turns on when the signal reaches it.

Circuit Construction Kit (DC)

An electronics kit in your computer! Build circuits with resistors, light bulbs, batteries, and switches. Take measurements with the realistic ammeter and voltmeter. View the circuit as a schematic diagram, or switch to a life-like view.

Magnet and Compass

Ever wonder how a compass worked to point you to the Arctic? Explore the interactions between a compass and bar magnet, and then add the earth and find the surprising answer! Vary the magnet's strength, and see how things change both inside and outside. Use the field meter to measure how the magnetic field changes.

Magnets and Electromagnets

Explore the interactions between a compass and bar magnet. Discover how you can use a battery and wire to make a magnet! Can you make it a stronger magnet? Can you make the magnetic field reverse?

Faraday's Electromagnetic Lab

Play with a bar magnet and coils to learn about Faraday's law. Move a bar magnet near one or two coils to make a light bulb glow. View the magnetic field lines. A meter shows the direction and magnitude of the current. View the magnetic field lines or use a meter to show the direction and magnitude of the current. You can also play with electromagnets, generators and transformers!

Generator Generate electricity with a bar magnet! Discover the physics behind the phenomena by exploring magnets and how you can use them to make a bulb light.
Circuit Construction Kit (AC and DC)

This new version of the CCK adds capacitors, inductors and AC voltage sources to your toolbox! Now you can graph the current and voltage as a function of time.

Three Charged Particles

The Three Charged Particles model displays three charged objects, one at each corner of an equilateral triangle. The charges have different magnitudes - your job is to rank the charges based on their magnitudes, from largest to smallest.  You can drag the charges around to see the effect on the net force on each charge.

Coulomb's Law and E-Field Package

The Coulomb's Law and Electric Field Package is a collection of models for electrostatics.  You can move charges around and see the force, you can observe the electric field generated by charge configurations and observe the motion of test particles in electric fields.

Electric Field and Potential Model

The Electric Field and Potential Model shows the electric field and potential for cylindrical and spherical symmetry. In both symmetries, there are co-centric charged surfaces where the outer surface is grounded. The model reports the force on a test charge (yellow) between the co-centric surfaces as well as the voltage.

Parallel Plate Capacitor

The Parallel Plate Capacitor model displays a parallel-plate capacitor which consists of two identical metal plates, placed parallel to one another. The capacitor can be charged by connecting one plate to the positive terminal of a battery and the other plate to the negative terminal.

RC Circuit

RC Circuit models the dynamical behavior of a voltage source attached in series to a resistor and capacitor. The source voltage can be chosen to be either a 10 volt sinusoidal or square wave with an adjustable frequency.

Magnetic Bar Field

The Magnetic Bar Field Model shows the field of a bar magnet and has a movable compass that reports the magnetic field values. The bar magnet model is built by placing a group of magnetic dipoles along the bar magnet.

Charge in a B-Field

The Charge In B-Field model simulates moving charged particles in two identical magnetic field regions separated by a zero magnetic field gap.

Three Current-Carrying Wires The Three Current-Carrying Wires model is a ranking task exercise involving the ranking of the current magnitudes in three parallel current-carrying wires.  The simulation displays the net force on each wire because of the other two wires. 
Rail Gun

The Rail Gun Model simulates a rail gun created by running current through long rods generating a magnetic field that accelerates a current-carrying cross-rod. The simulation shows the generated magnetic field.

Helmholtz Coils

The Helmholtz Coils Model shows a the magnetic field between two circular coils of wire.  The default configuration, known as a Helmholtz coil, sets the separation distance D equal to the coil radius R.  These values produce a nearly uniform magnetic field B between the coils

Falling Loop

The Falling Loop Model shows a conducting loop falling out of a region of uniform magnetic field. It plots the velocity of the loop as a function of time. Users can change the size and orientation of the loop as well as the extent and location of the uniform field.

Electric Generator

The Electric Generator Model shows a simple electric generator made from a conducting loop rotating in a uniform magnetic field and connected to an ammeter. The model shows a plot of the magnetic flux and induced current.

RLC Circuit

The RLC Circuit model simulates a resistor, capacitor and inductor in series with either a sinusoidal or square wave voltage source and plots the time dependence of the voltage drops across each element. Users can vary the resistance, capacitance, inductance and source frequency.

EM Radiation

The EM Radiation program displays the electric field vectors (in the x-y plane) and magnetic field contours (for the field in the z direction) calculated from the Lienard-Wiechert potentials for a charged particle.  The default scenario shows the resulting radiation from a charged particle in simple harmonic motion.

Electric Field Lines Illustrating representing an electric field with field lines.
E-Field of Oscillating Charge Illustrating representing an electric field with field lines.
Circuit / Water Analogy

A simple DC circuit has a DC voltage source lighting a light bulb. Also shown is a hydraulic system in which water drives a turbine. The two systems are shown to be similar.

Light Switch A simple animation of how a common light Switch works.
Simple Buzzer A simple buzzer consisting of a battery, a flexibile metal strip, a piece of iron, and some wire.

The Java Applets were taken either from PhET or Open Source Physics.

The Flash Animations were all taken from David M. Harrison from the University of Toronto.