These are some educational java applets I wrote to help visualize various concepts in math, physics, and engineering. You should be able to view them with any Java-capable browser.

If you don't have Java, get the Java plug-in.


Oscillations and Waves

Ripple Tank (2-D Waves) Applet
Ripple tank simulation that demonstrates wave motion, interference, diffraction, refraction, Doppler effect, etc.
2-D Waves Applet
Demonstration of wave motion in 2-D.
3-D Waves Applet
Demonstration of wave motion in 3-D.
Coupled Oscillations Applet
Demonstration of longitudinal wave motion in oscillators connected by springs.
Dispersion Applet
Dispersion and group velocity.

Acoustics

Loaded String Applet
Simulation of wave motion of a string.
Rectangular Membrane Waves Applet
Vibrational modes in a 2-d membrane.
Circular Membrane Waves Applet
Vibrational modes in a 2-d circular membrane (drum head).
Bar Waves Applet
Bending waves in a bar.
Vowels Applet
The acoustics of speech.
Box Modes Applet
Acoustic standing waves in a 3-d box.
Acoustic Interference Applet
Generates audio interference between your speakers.

Signal Processing

Fourier Series Applet
Frequency analysis of periodic functions.
Digital Filters
Filters digital signals and plays the output on your speakers.

Electricity and Magnetism: Statics

2-D Electrostatics Applet
Demonstrates static electric fields and steady-state current distributions.
2-D Electrostatic Fields Applet
Demonstrates electric fields in various 2-D situations; also shows Gauss's law.
3-D Electrostatic Fields Applet
Demonstrates electric fields in various 3-D situations.
3-D Magnetostatic Fields Applet
Demonstrates magnetic fields in various situations.

Electrodynamics

2-D Electrodynamics Applet (TE)
Demonstrates electromagnetic radiation.
2-D Electrodynamics Applet (TM)
Demonstrates electromagnetic radiation, induction, and magnetostatics.
Analog Circuit Simulator Applet
Demonstrates various electronic circuits.
Cavity Modes Applet
Electromagnetic waves in a 3-d rectangular cavity.
Waveguide Modes Applet
Electromagnetic waves in a waveguide.
Antenna Applet
Generates antenna radiation patterns.
Fresnel Diffraction Applet
Generates Fresnel diffraction patterns.

Quantum Mechanics

Hydrogen Atom Applet
Shows the orbitals (wave functions) of the hydrogen atom.
Molecular Orbitals Applet
Shows the orbitals (wave functions) of the hydrogen molecular ion.
1-D Quantum Mechanics Applet
Single-particle quantum mechanics states in one dimension.
1-D Quantum Crystal Applet
Periodic potentials in one dimension.
2-D Quantum Crystal Applet
Periodic potentials in two dimensions.
1-D Quantum Transitions Applet
Radiative transitions (absorption and stimulated emission) in one dimension.
Atomic Dipole Transitions Applet
Radiative transitions (absorption and stimulated emission) in atoms.
2-D Rectangular Square Well Applet
Rectangular square well (particle in a box) in two dimensions.
2-D Circular Square Well Applet
Circular square well in two dimensions.
2-D Quantum Harmonic Oscillator Applet
Harmonic oscillator in two dimensions.
Quantum Rigid Rotator Applet
Particle confined to the surface of a sphere.
3-D Quantum Harmonic Oscillator Applet
Harmonic oscillator in three dimensions.

Linear Algebra

Dot Product Applet
Demonstrates the dot product or scalar product of two vectors.
Matrix Applet
Demonstrates 2-d transformations using a matrix.

Vector Calculus

2-D Vector Fields Applet
Demonstrates various properties of vector fields, including divergence and curl, etc.
3-D Vector Fields Applet
Demonstrates vector fields in 3 dimensions. Includes the Lorenz Attractor and Rossler Attractor.

Thermodynamics

Gas Molecules Simulation Applet
Demonstrates the kinetic theory of gases.
Thermal Camera Pictures
Some sample pictures taken with a thermal (infrared) camera. (This is not an applet but I thought I'd throw it in here anyway.)

Miscellaneous

A Sense of Scale
Provides a visual comparison of various distances, from very small objects like protons and electrons, to distances between galaxies. (Not an applet, but I thought I'd include it here anyway.)
Ordinary Differential Equations Applet
Visual differential equation solver.
Euler's Equation Applet
Demonstrates Taylor series expansion of complex exponentials.

Licensing info.

Links to other educational sites with math/physics-related information or java applets useful for teaching:

And when you get tired of learning, here is some fun stuff:







java@falstad.com