Introductory Physics: Fields

PHY 272 (PHY 272 H)- Spring 2014

Instructor: Paulo Bedaque, Physics Science Complex, room 3147

Office hours:     TuTh 12:30pm - 1:45pm

F 12:00pm - 12:50pm



Textbook: Either "Electricity and Magnetism", E. Purcell, 2nd edition or "Electricity and Magnetism", E. Purcell & D. Morin, 3rd edition. These books are very similar but the third edition uses the SI unit system we will use in lecture. Contrary to other topics, formulae in electromagnetism actually change in different systems of units so it's convenient to have the third edition. In any case I'll show you how to translate formulae from one system to the other in class. The lectures will not follow the book closely and the book (either edition) is only recommended, not required. The level of mathematical sophistication required in this class is somewhat above what most students start the semester with. I'll help you with multivariable and vector calculus during the semester and a good source for these topics is the free, online textbook "Mathematical Tools for Physics", by J. Nearing, that can be found here. Chapters 8, 9 and 13 are the relevant ones.

Discussion group: Questions and comments should, if at all possible, be made through Canvas. You can do it anonymously if desired. This way your question, and my and your colleague's answers, can help all other students. Canvas is not good at mathematical equations so, depending on how things go, we may migrate to Piazza.

Grades: The grade will be based on frequent homeworks (10%), and three in-class exams (30% each).

Syllabus and objectives: The goal of this class is to introduce the concept of electromagnetic fields and the mathematics used in their description, understand the laws governing them (Maxwell's equations) and apply these laws to a large variety of situations arising in several branches of physics, astrophysics and technology. The specific topics covered and the level of sophistication will be comparable to Purcell's book but it's unlikely we will be able to cover all chapters, in which case we will skip most of electric oscillating current circuits (discussed in depth in PHY272), dielectrics and magnetic materials.


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Tentative Syllabus


Charge and electric field

Gauss' law; flux

Electric potential; line integral; gradients, divergence and curl; divergence and Stokes theorem



Currents and Ohm's law; energy dissipation

Ampere's law

Electromagnetic induction

Faraday's law; inductance and self-inductance

Alternating current circuits

Maxwell's equations

Displacement current

Maxwell's equaiton in integral and differential form

Electromagnetic waves; energy transport

Electric and magnetic fields in matter

Electric dipoles, polarization and dielectrics

Magnetic dipoles, magnetization, ferromagnetics, paramagnetics and diamagnetics


Origins of relativity and the relativistic invariance of Maxwell's equations


Useful links:

Some people like " Div, Grad, Curl, and All That: An Informal Text on Vector Calculus", Fourth Edition, H. M. Schey.

Make sure you play with the applet to find the field configurations generated by different charges distributions. It is the best way to get some intuition for the Coulomb law. There are other, better versions around the web. Let me know if you find a particularly good one.

An amusing proof that the line integral of a gradient over a closed contour must vanish (or, what is the same, taht the curl of a gradient must vanish).

Undergraduate Peer Tutoring

There is a new tutoring service available to undergraduate physics majors in the introductory courses, provided by physics majors who have already completed the introductory series. The tutoring service is available Monday through Friday, from 4pm - 6pm in PHYS 1204 (the room next to the undergraduate student lounge). The tutors are happy to provide homework help and discuss course topics in general with students at no cost.

If you have any questions, please direct them to Hannalore Gerling-Dunsmore at .

Academic Integrity:  The University of Maryland, College Park has a nationally recognized Code
of Academic Integrity, administered by the Student Honor Council. This Code sets standards for
academic integrity at Maryland for all undergraduate and graduate students. As a student you
are responsible for upholding these standards for this course. It is very important for you to be
aware of the consequences of cheating, fabrication, facilitation, and plagiarism. For more information on the Code of Academic Integrity or the Student Honor Council, please visit