# Interactive animated Java Applets

The following interactive Java Applets demonstrate several aspects of electro- and magnetostatics, as well as electrodynamics.

All applets except the “Static Fields II” applet are the property of Paul Falstad.

# Static Fields

This java applet demonstrates electrostatics and static current distributions in two dimensions.

When the applet starts up you will see the electric field of a single positive charge. The charge can be dragged around the screen with the mouse.

# Static Fields II

This Java applet illustrates the distribution of electrostatic fields and was created at TEMF. The electrostatic field of an arbitrary number of point charges is analytically calculated and displayed.

Furthermore, electrostatic problems with fixed potentials, different dielectrics, different boundary conditions, and many other properties can be considered. To solve the static problem, the finite integration method in the 2D formulation is used. As an equation solver, the Gauss-Seidel method is used. As a data structure for the sparse matrices HashMaps with primitive data types GNU Trove </ a> are used. You can see the numerically calculated distribution of a potential in free space with PEC boundary conditions.

# Standing Waves

This Java applet is a simulation that demonstrates standing waves in a 3D cube or in a resonant cavity.

Different modes are analyzed. Electric and magnetic fields can be displayed in many ways.

# Electrodynamics (TE)

This java applet is a simulation that demonstrates electrodynamics in two dimensions, including setups which demonstrate electromagnetic waves, reflection at conductors, radiation from antennas, standing waves, waveguides, and diffraction. This is the TE version of the applet.

# Electrodynamics (TM)

This java applet is a simulation that demonstrates electrodynamics in two dimensions, including setups which demonstrate electromagnetic waves, reflection at conductors, radiation from antennas, standing waves, waveguides, and diffraction. This is the TE version of the applet.

# Antenna Radiation Patterns

This java applet is a simulation that demonstrates electromagnetic waves generated by antennas and antenna arrays in two dimensions.

# Dot Product

This java applet demonstrates the dot product, which is an important concept in linear algebra and physics. The goal of this applet is to help you visualize what the dot product geometrically.