
An unusual 7-body orbit for gravitationally interacting particles.
Easy Java Simulations simplifies the modeling process by breaking it into activities: (1) documentation, (2) modeling, and (3) interface design. The html-based documentation is accessed by selecting Description. The physics is accessed by selecting Model which provides access to the data and the methods (Java code) by which the model can change. A plot is a visual representation of data and is an example of a View. Because it is possible to have multiple views of the same data and because the model and its views are controlled by buttons and other user interface components, Ejs provides a graphical drag-and-drop editor for these objects thereby eliminating much coding. The Ejs model-view-controller paradigm is well known in computer science and provides a solid foundation for software development.
Easy Java Simulations promotes an integrated understand of the modeling process by exposing and providing access to the underlying assumptions in the physical model. It encourages revision and testing of the model and the distribution of the model including narrative and documentation. Finally, it is both simple to use and sufficiently advanced to handle complex models that occur in professional practice. Advanced models are included in this package without explanation to demonstrate how the physics principles presented in this tutorial can are applied to more complex systems.
Ball in Wedge models the dynamics of a ball falling and bouncing in a symmetric wedge. The ball's free-fall trajectory
and bounce are discussed in any introductory physics textbook yet the ball-wedge system exhibits a rich array of periodic and chaotic behavior and is of
current research interest.
Hard Disk Gas extends the collision model to multiple particles. Particles move with constant velocity until a collision
detected. Although collision detection is not a very efficient computation algorithm for this problem, it is straightforward, accurate
and fast-enough for small numbers of particles to show the physics that gives rise to this simple gas model.
Hard Sphere Gas extends the Hard Disk Gas model to three dimensions.
Pendulum 3D models a spherical pendulum in three dimensions.
Oscillator Chain models a linear array of coupled harmonic oscillators.
N-Body solves the gravitation N-body problem for unusual orbits.