"I have also a paper afloat, with an electromagnetic theory of light, which, till I am convinced of the contrary, I hold to be great guns."
Welcome to Physics 351! In this class we will study charges, currents, electric and magnetic fields, and their interactions. Much of the physics is expressed in a single, remarkable set of equations
\begin{gather} \vec{\nabla} \cdot \vec{E} = \frac{1}{\epsilon_{0}} \rho \vphantom{\frac{\partial\vec{B}}{\partial t}} \\ \vec{\nabla} \times \vec{E} + \frac{\partial\,\vec{B}}{\partial \,t} = 0 \\ \vec{\nabla} \cdot \vec{B} = 0 \vphantom{\frac{\partial\vec{B}}{\partial t}}\\ \vec{\nabla} \times \vec{B} - \mu_{0}\,\epsilon_{0}\,\frac{\partial\,\vec{E}}{\partial\,t} = \mu_{0}\,\vec{J} \end{gather}This formulation of electromagnetism is due primarily to the Scottish physicist James Clerk Maxwell. His equations, in one form or another, describe phenomenon ranging from the propagation of light to the deflection of a compass needle by a magnetic field.
James Clerk Maxwell (1831-1879)
The impact of Maxwell's equations extends well beyond electromagnetism: the Theory of Special Relativity is hidden inside them, and they are the prototype for a unified description of the basic forces of Nature.
Syllabus
Basic information about our schedule, homework assignments, grades, and more can be found below. Click here to download a pdf version of the full syllabus. The syllabus has more detailed information, and you should be familiar with the policies and rules it describes.
Fall 2025 Schedule
At a minimum we will cover the first seven chapters of the textbook and parts of chapters 8 and 9. The timeline below is an estimate of how we would do that.
| Week | Dates | Chapter |
|---|---|---|
| 1 | August 25, 27, 29 | 1 |
| 2 | September 1, 3, 5 | Labor Day; 1, 2 |
| 3 | September 8, 10, 12 | 2 |
| 4 | September 15, 17, 19 | 2 |
| 5 | September 22, 24, 26 | 3 |
| 6 | September 29; October 1, 3 | 3, Exam 1 |
| 7 | October 6, 8, 10 | Fall Break; 3 |
| 8 | October 13, 15, 17 | 4 |
| 9 | October 20, 22, 24 | 4, 5 |
| 10 | October 27, 29, 31 | 5 |
| 11 | November 3, 5, 7 | 5, 6 |
| 12 | November 10, 12, 14 | 6, Exam 2 |
| 13 | November 17, 19, 21 | 7 |
| 14 | November 24, 26, 28 | 8; Thanksgiving |
| 15 | December 1, 3, 5 | 9 |
| 16 | December 11 | Final Exam (1-3 pm) |
This is the basic set of material we have to cover. But if you are engaged and active in class we can go faster, which will let us cover additional (interesting!) material from chapters 10 and 11.
Assignments
Homework is assigned each week (except for exam weeks) and collected the following week. With a few exceptions it will usually be due on Monday at the beginning of class. That way you can ask questions during our Friday discussion section.
Only some of the problems from each assignment will be graded. I won't tell you which ones, so you need to complete them all. We will talk more about how this works in class. Current and past assignments are listed below. You can see solutions for some (not all) problems, but they are not available for download. Please stop by my office if you'd like to see solutions for a particular assignment.
Assignment 1
Review of Vector Analysis
Due Wednesday, August 28
This revidw assignment is due at the beginning of our second class. Starred problems with red titles (5 and 6 on this assignment) are optional – they will not be graded, but you should try them.
Working with classmates on these assignments is encouraged! But you should only hand in work you've completed on your own. If your solution looks just like someone else's work then you need to go back and redo it from scratch. If you can't explain each step of your solution then you haven't completed the problem on your own. Remember: the only way to be ready for the exams is to do the homework yourself.
Never hand in an assignment that has been copied from a solutions manual or LLM output. You won't learn anything that way, and it will earn you a grade of zero for the assignment. If it happens more than once it will be reported to the Department Chair and the Dean. Consider yourself warned. Click here to see the College of Arts and Sciences Statement on Academic Integrity.
Grades
Grades in this course are mostly based on homework assignments and exams. The weekly homework grades contribute 35% of your final grade in the class, and two exams (October 3 and November 14) count 15% each. A cumulative final exam (December 11, from 1 - 3 pm) is worth 30%. The remaining 5% depends on attendance and participation. Asking questions, taking advantage of office hours, and attending both lectures and discussion sections will earn you the full 5%. Check the syllabus for more details.
References
The main text for the class is Introduction to Electrodynamics by David Griffiths. The book is currently in its 5th edition, but a copy of the 3rd or 4th edition is perfectly good for this class. The tone of the book is casual and most students find it very accessible. When I was an undergraduate we used the textbooks by Wangsness and Purcell. They might be helpful if something in Griffiths isn't clear. A more advanced treatment is Classical Electrodynamics by J. D. Jackson. It is used in practically every graduate E&M course.
- Introduction to Electrodynamics
David J. Griffiths
- Electromagnetic Fields
Roald K. Wangsness
- Electricity and Magnetism
Edward M. Purcell
- Classical Electrodynamics
J.D. Jackson
Griffiths' book has a very complete (for our purposes) discussion of vector calculus. If you'd like to see this material in more detail, I recommend the math methods book by Boas, or the book by Riley, Hobson, and Bence. There's also the graduate textbook by Arfken and Weber. It's more advanced, but your Math Methods class gave you all the preparation you need.
- Mathematical Methods in the Physical Sciences
Mary L. Boas
- Mathematical Methods for Physics and Engineering
K.F. Riley, M.P. Hobson, and S.J. Bence
- Mathematical Methods for Physicists
George Arfken and Hans Weber
The Feynman Lectures on Physics, which include a few nice discussions about some of the things we'll talk about in class, are available online. The Physics Club should also have a copy downstairs.
Lecture Notes
A full set of lecture notes for this class is available on Sakai, organized in the “Class Notes” folder under the “Resources” tab. Click here to access the notes.
In the same folder you will also find notes on topics from Math Methods. These might be helpful if you want to brush up on orthogonal coordinate systems or vector calc.
You may not distribute either set of notes. Please see the syllabus for more details.
Notes
From time to time I will supplement material from the textbook with my own notes, which will be posted below.
The Helmholtz Theory of Vectors
These notes give a brief overview of the Helmholtz theory of vectors, and some important facts about vectors with vanishing divergence or curl. A more complete discussion is given in Appendix B of the text. Some of these ideas will be developed more fully in later chapters.
A quick review of a few integrals that show up again and again on the homework.
The Dirac delta can be a little tricky, so here are some notes that expand on our discussion in class.
Examples of Line, Surface, and Volume Integrals
A quick review of line, surface, and volume integrals with several examples. The part on volume integrals isn't finished, but the stuff on line and surface integrals is there.
This is a basic review of line integrals – what they are, how to evaluate them, etc. It may be useful if you're a little rusty on this topic. The file is big (about 22 MB) because of the embedded plots. Let me know if you find typos or mistakes!
E&M Stress Relief
Sometimes E&M wears you out, and the only thing that can get you back on track is a picture of an adorable kid doing physics. Here you go.
