In the Electric Field Plotting Experiment, the potential contours are determined by a series of voltage measurements. In these simulations, charges are confined to shapes corresponding to the conductor configurations explored in the lab. The individual charges gradually settle to an equilbrium configuration, and the resulting charge configuration creates an electric field (and corresponding potential contours) that should correspond to those observed in lab.
Select on of the conductor configurations using the buttons on the left hand side of the window. Press the play buton to start the simulation. Observe how the charges rearrange as they settle into an equilibrium configuration. After the charges have "settled down", check the boxes for vector field and contour. How do the simulation results compare with your results from lab? Compare the two simulations for the parallel plate geometry. What are the differences in the geometies and in the resulting fields?
The last two configurations illustrate the effect of isolated conducotrs which are overall charge neutral.
You can create your own configurations by building walls and placing charges. For example, using the "build wall" option on the right panel, click within the simulation panel to locate successive ends of the walls which mark the boundaries of the conductor. Make sure the the walls form a closed container! Place charges (a group at a time) by selecting the type of charge from the right panel and clicking within the simulation panel to place the group of charges. (Each charge is automatically given a random velocity)
Adapted by Mike Gallis from the Particles and Walls simulation by Francisco Esquembre