(Lecture: 40 minutes)

See §11.4 and §11.5 of the text.

On the one hand, this lecture provides new insight into the unification of electrity and magnetism. On the other hand, the treatment is not elementary, and it is hard to keep students focused. One possibility might be to summarize the key results without deriving them, referring the interested student to the text. Another might be to skip this material altogether. At the moment, however, there is no good alternative for the last 2-hour block in the typical paradigms schedule.

A possible alternative would be to use the preceding lecture as an activity, then either summarize or skip this lecture as part of an extended wrapup.