VIEW or DOWNLOAD ejs xml source
then click to translate strings for selected locale.


Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop.

[b]Particles and Walls [/b]
   This is perhaps the most complex and complete simulation that I have built as examples of use of Ejs.
It simulates the electrical interaction of charged particles , both positive and negative ones, among themselves and also with physical (non-charged) barriers or walls.


     The user can build any configuration she is interested in and let the simulaton run. Of special interest is the visualization of the vector field generated by the charged particles and how it evolves dynamically.


   

I also included a visualization of the equipotential lines in the plane and of the potential in 3D. Just to show some of the visualization capabilities of Ejs.


   

The minimum and maximum of the potential are recomputed every time you switch on and off the visibility of the contour, so, when adding new particles, it is a good idea to hide the contour, add the particles, let  the simulation play for a while, until a more or less stable situation has been reached, and then show the contour.


   

Please notice that (except when running as an applet) you can prepare and save different configuration of particles and walls. These  configuration can be read later on by your students (even when running as an applet).



[b]     Activities[/b]
   There are a lot of possible activities, but my favourite one is to build a closed wall, place inside a number of charges of the same sign and let the simulation run.
   

From time to time, freeze the particles and you will get with a final configuration in which all particles are at the walls.


   

   Then, place a new one in the middle and see what happens. Relate this with applicable theory...    
Author : Francisco Esquembre

   
 

   

   Date : February 2002