This simulation shows you what the electic field looks like for an electron thats moving near the speed of light. You can use the direction pad to kick the electron around. It will bounce off of the walls. Look at how the field bends when the electon bounces. You can also move it around by clicking and dragging inside the circle to make a tether. The tether is like a rubber band that will pull on the electron. Look at how the field lines curve smoothly when the electon accelerates slowly.
You can also do some preset motions using the Polygon Side number scroller and the initiate button. Set the side scroller to 3 for a triangular bounce pattern, 4 for a square, and so on. Try turning the slider all the way up for circular motion, or all the way down for oscillatory motion!
Turning up the tether stiffness can make it hard to control, so be careful! If you are making circular motion with high velocity, the lines may start to look messy. If it does this use the high res option, but otherwise leave it off or it will be really slow :).
*Performance Tips* The simulation runs fairly well on a wide range of computers, slow and fast, Windows and Mac. If it is slow on your computer, however, there are a few things that drastically affect the running speed. Turn down the number of field lines and turn the running speed all the way up. Switching into a black and white color scheme will also improve run speed slightly. Also, as mentioned before, keep the high res checkbox off, it slows it down DRASTICALLY.
This applet was written by Andrew Flinders (WSU student), fall 2011.