# PHYS 381 Electromagnetism I

**Instructor**: Dr. Hanna channa@boisestate.edu (208) 426-3775 MP-425

**Office Hours**: MW 4:00-5:00pm

**URL**: https://www.boisestate.edu/physics/regular-faculty/hanna/phys-381/

**Classroom**: MP-301 Time: MWF 10:40-11:30am

**Prerequisites**: MATH 275, MATH 333, PHYS 212

**Required preparation: thorough understanding and ability to use vector calculus, including
gradient, divergence, curl, and laplacian in cartesian, cylindrical, and spherical coordinates;
mastery of all electrostatics and magnetostatics concepts and techniques from PHYS 212**

Text: *Introduction to Electrodynamics,* by David J. Griffiths, 3rd edition

• Corrections to the first printing (fixed in the second printing, summer 1999)

• Corrections to the second printing, January 22, 2000

• Corrections to the third printing, August 4, 2000

• Corrections to the fifth printing, June 26, 2001

• Corrections to the tenth printing, September 1, 2004

• Corrections to the eighteenth printing, August 20, 2009

Vectors & Derivatives; Calculus; Curvilinear Coordinates reading: 1.1-1.2.5 (1-20); 1.2.6-1.3 (19-38); 1.4 (38-44)

**Part 1: Vector Analysis and Electrostatics**

**(Exam 1 over Chapters 1 and 2 on Wed Sep 29)**

**H1 due 8/30**: 1.13, 1.16, 1.18, 1.25, 1.28, 1.32, 1.33, 1.39, 1.42

(Fri Sep 3 is last day to dropwithout a W.)

Dirac Delta Function & Vector Fields; Electric Field & Field Lines; Gauss’s Law

reading: 1.5-1.6 (45-54); 2.1, 2.2.1-2.2.2 (58-70); 2.2.3 (70-74)

**H2 due 9/8**: 1.44, 1.47, 2.4, 2.5, 2.6, 2.103.9/6(Holiday); Electric Potential & Poisson’s Eq.; Electrostatic Boundary Conditions

reading: (No Class); 2.2.4-2.3.3 (76-83); 2.3.4-2.3.5 (83-90)

**H3 due 9/13**: 2.13, 2.15, 2.16, 2.21, 2.23, 2.244.9/13Electrostatic Energy; Conductors; Capacitors

reading: 2.4.1-2.4.2 (90-93); 2.4.3-2.5.2 (93-101); 2.5.3-2.5.4 (102-106)

**H4 due 9/20**: 2.27, 2.28, 2.31, 2.32, 2.33, 2.345.9/20Review; Laplace’s Equation; Uniqueness Theorems

reading: Chaps. 1-2 (1-109); 3.1.1-3.1.4 (110-114); 3.1.5-3.1.6 (116-121)

**H5 due 9/27**: 2.35, 2.37, 2.39, 2.40, 2.46, 3.16.9/27

(Fri Oct 1 is last day to drop with a W.)

Method of Images; **EXAM 1 (Wed Sep 29)**; Conducting Sphere

reading: 3.2.1-3.2.3 (121-124); (Exam 1); 3.2.4 (124-125)

**H6 due 10/4**: 3.6, 3.7, 3.8, 3.10 **Part 2: Special Techniques and Dielectrics**

**(Exam 2 over Chapters 3 and 4 on Wed Nov 3)**7.10/4Laplace’s Eq. I (Ex. 3.3); Laplace’s Eq. II (Ex. 3.4-3.5); Laplace’s Eq. III (Ex. 3.6-3.7)

reading: 3.3.1a (127-132); 3.3.1b (132-136); 3.3.2a (137-141)

**H7 due 10/11**: 3.12 3.13, 3.15, 3.18, 3.198.10/11Laplace’s Eq. IV (Ex. 3.8-3.9); Multipole Expansion; Electric Dipole

reading: 3.3.2b (141-144); 3.4.1-3.4.2 (146-150); 3.4.3-3.4.4 (151-154)

**H8 due 10/18**: 3.22, 3.26, 3.27, 3.32, 3.419.10/18Polarization; Bound Charges; Dielectrics

reading: 4.1 (160-166); 4.2 (166-175); 4.3-4.4.1 (175-184)

**H9 due 10/25**: 4.4, 4.10, 4.11, 4.15, 4.17, 4.1810.10/25Dielectric Boundaries; Energy and Force for Dielectrics; Review

reading: 4.4.2 (186-190); 4.4.3-4.4.4 (191-196); Chaps. 3-4 (110-201)

**H10 due 11/1**: 4.20, 4.25, 4.26, 4.27, 4.2811.11/1Magnetic Fields and Forces; **EXAM 2 (Wed Nov 3)**; Currents

reading: 5.1.1-5.1.2 (202-207); (Exam 2); 5.1.3 (208-214)

**H11 due 11/8**: 5.1, 5.4, 5.5, 5.6 **Part 3: Magnetostatics and Magnetism in Matter**

**(Exam 3 over Chapters 5 and 6 on Wed Dec 15)**

** **12.11/8Biot-Savart Law; Div & Curl of Magnetic Field; Ampere’s Law

reading: 5.2 (215-219); 5.3.1-5.3.3a (221-226); 5.3.3b (226-229)

**H12 due 11/15**: 5.9, 5.10, 5.11, 5.13, 5.1413.11/15Solenoids and Toroids; Magnetic Vector Potential; Magnetic BCs and Dipole Moment

reading: 5.3.3c-5.3.4 (229-233); 5.4.1-5.4.2 (234-238); 5.4.2-5.4.3 (240-246)

**H13 due 11/29**: 5.24, 5.25, 5.26, 5.35, 5.36 11/22

**THANKSGIVING (11/22–11/26)**

** **14.11/29Magnetization; Bound Currents; Auxiliary Field

reading: 6.1 (255-263); 6.2 (263-268); 6.3 (269-274)

**H14 due 12/6**: 6.1, 6.7, 6.8, 6.9, 6.1215.12/6Magnetic Susceptibility; Ferromagnetism; Review

reading: 6.4.1 (274-277); 6.4.2 (278-281); Chaps. 5-6 (202-284)

**H15 due 12/13**: 6.14, 6.16, 6.17, 6.2516.12/13** EXAM 3 (Wed Dec 15, 10:30am-12:30pm, MP-301)**

**GOALS:** To obtain a basic understanding of the key concepts of electrostatics and magnetostatics based on the static limit of Maxwell’s Equations, using the formalism of vector calculus throughout, and to prepare students for undergraduate electrodynamics (PHYS 382) and graduate-level electrostatics and magnetostatics. The course objectives will be accomplished through lecture and discussion of selected topics in class, and by students working through the assigned parts of text, including all textbook examples and all assigned homework problems. Assessment will come from exams and assigned homework.

**SYLLABUS:** The syllabus describes the **intended** progression of the course. The syllabus and homework assignments will be revised as needed. Changes to the syllabus and the homework assignments will be posted on the course web page,https://www.boisestate.edu/physics/regular-faculty/hanna/phys-381/, which should be checked frequently for updates.

**EXAMS: 90%** of your grade is based on the exams. The exams are based on the textbook readings, the numbered examples in the text, the homework, extra-credit problems, and the class lectures. **ALL EXAMS WILL BE COUNTED, AND NO MAKE-UP EXAMS WILL BE GIVEN.** There will be three exams, worth 30% each. **Only simple scientific calculators allowed during exams**: no calculators that are capable of graphing, integration, differentiation, or symbolic algebra are allowed. You may bring one 8.5″ by 11″ **sheet of formulas** for each exam, with formulas on both sides, plus the formula sheets from your previous PHYS 381 exams. All formula sheets must be labeled at the top with your name and the exam number, be **signed and handwritten** by you, and be turned in with your exam. Your formula sheet should contain **only numbered formulas** from those sections of the chapters that are covered on the exam, and you must write the textbook equation number next to each formula. No other formulae, comments, drawing, or other information are allowed on the formula sheet. It is your responsibility to know the meaning of every symbol on your formula sheet, and to understand the meaning, applicability, and use of every equation that you include on your formula sheet.

**HOMEWORK: 10%** of your grade is based on the homework. Hand in what you have on the due date, at the beginning of class. **NO LATE HOMEWORK ACCEPTED.** ** Start homework assignments early (ASAP) because they are challenging and time-consuming.** Homework problems will form the basis for many of the exam problems. Look over your graded homework carefully and make sure you can work and understand every assigned homework problem. You are strongly encouraged to talk to the instructor about homework problems that you do not understand.

**LECTURES & ASSIGNED READINGS:** Class lectures relate closely to the assigned readings in the text. Students are expected to attend all lectures and participate actively in class. Consult the syllabus and read the assigned pages **before and after** the material is covered in class. **Carefully work through all numbered examples in the assigned reading.** As you read, write down any questions you have about the reading and the numbered examples, and ask questions in class.

**EXTRA CREDIT:** Extra credit problems that are an integral part of the textbook readings may be given from time to time in class. They should be handed in at the due date of the earliest upcoming homework assignment, with that homework assignment. In addition, the first person who e-mails the instructor with an accurate finding (and proposed correction) of an error in the text that has not already been listed in the Author’s Corrections (see the web links near the beginning of the syllabus) will also receive extra credit. Note that **the total possible amount of extra credit is very small**, so priority should be given to exam preparation and to homework; however, the extra-credit problems may be relevant to exam questions and are exercises that should be done in order to follow the reading assignments.

**ACADEMIC HONESTY:** Although you are encouraged to discuss the class lectures, readings, and assignments with your classmates, all work that you turn in must be your own. **NO CHEATING OR PLAGIARISM (PRESENTING OTHER PEOPLE’S WORK AS IF IT WERE YOUR OWN) WILL BE TOLERATED, INCLUDING ANY USE OF HOMEWORK SOLUTIONS FOUND ON THE WEB.** If you make use of any sources besides the class lectures or textbooks, you must provide explicit written references to the sources you use. Failure to follow this rule or any others listed in the Student Code of Conduct could have drastic consequences, including (but not limited to) ejection from the course with a failing grade.

**GRADING:** A- to A+ = 90 – 100, B- to B+ = 75 – 90, C- to C+ = 60 – 75, D- to D+ = 45 – 60