With this simulation, you can investigate the implications of Gauss’ Law as it applies to charged spheres made from conductive material. You can use a thin-walled spherical shell as well as a thick-walled shell – compare the fields obtained to the electric field from a point charge. The view shown in the simulation represents a two-dimensional slice through the center of the shells, which is why they look like circles.

Here are some things to consider.

1. | Gauss’ Law states that inside a uniformly charged spherical shell, the electric field due to the charge on the shell is zero. Verify that with the simulation. Under what condition is it possible to have a non-zero electric field inside a uniformly charged spherical shell?
2. | Another implication of Gauss’ Law is that the electric field outside a uniformly charged spherical shell, with a net charge Q, is the same as the field from a point charge Q. Verify that with the simulation by measuring the electric field created by the inner shell, and then replacing the inner shell by the point charge. If the point charge has the same charge as the inner shell did, is the field the same in the region outside the inner shell?
3. | Set the charge on the outer shell to -1 mC, and the other two charges to zero. How is the charge distributed on the outer shell? Keeping the charge on the outer shell at -1 mC, give the inner shell a charge of +1 mC. How is the charge distributed on the outer shell now? What happens if you increase the charge on the inner shell?
4. | Using both spherical shells as well as the point charge, arrange it so there is an electric field inside the inner shell pointing toward the center, no electric field between the inner and outer shells, and an electric field outside the outer shell that points away from the center of the shells.
5. | How can you maximize the magnitude of the electric field in the region outside the outer shell?