Symmetry and Gauss' Law

Related Physics Education Research

None that I know of.

Overview of Worksheet

The purpose of this worksheet is to help students understand the symmetry arguments that are key in the application of Gauss' Law to find the electric field for a sphere, infinite cylindar or infinite plane of charge. This is not a lab - no data is taken, but I have found that these symmetry ideas do not come easily to students and this worksheet helps the students get a firm grasp on that part of the argument.

Approximate Time

One hour.

Required Student Background

Students need to be familiar with the concepts of electric fields and electric field lines and electric flux.

Connections to the Tutorials

This complements the tutorials on electric field and flux. The ideas of symmetry are not explored in detail there, but the concept of flux is treated in detail.

Required Equipment

Styrofoam balls in shape of spheres, sheets cylinders and cubes and toothpicks.

Evaluation of Worksheet

At the end of the class students were able to explain why the electric field due to a uniform cube of charge is not constant on a known surface (e.g. a cube or a sphere).