PHYSICS 110B

ELECTROMAGNETISM 2

Winter Quarter 2009

ANNOUNCEMENTS:


FINAL EXAM: The final exam has been graded, and course grades have been posted on GOLD.  The exams will be given back after the first meeting of 110C on Monday, 30 March 2009 at 11 am in Phelps 3523.  Or, you can drop by Prof Gwinn's office during office hours.


Fusion Power: Lawrence Lidsky wrote an influential article, "The Trouble With Fusion", published in MIT's Technology Review in 1983 (vol 86, no 7, pp 32-44).  Here's an online copy: http://www.askmar.com/Robert%20Bussard/The%20Trouble%20With%20Fusion.pdf
Robin Herman gives a reasonable description of the article and its historical repercussions in her book FUSION, with a pdf extract about Lidsky on the web.  Herman also tells some of the colorful history of the controlled-fusion effort.
Francis Chen's book Plasma Physics and Controlled Fusion gives a good account of plasma physics, accessible at an advanced-undergraduate level.
Shoichi Yoshikawa originated the idea of using one enormous loop (rather than a toroidal magnet) for a confining B-field. He called it OCLATOR, and described it in a journal article in Fusion Energy (accessible from on-campus).

Geomagnetic Field: http://www.geomag.us/info/declination.html shows the Earth's magnetic field, including a nifty animation of the field for the last few hundred years. Direct link to animation: http://www.geomag.us/info/Declination/magnetic_lines.avi

SYLLABUS

Prof. Carl Gwinn
2015E Broida Hall
(805)-893-2814
cgwinn(at)physics.ucsb.edu  (Note: Replace (at) with @ for email)
Office Hours: W 10:00 am - 11:00 am, Th 2:00 pm - 3:00 pm

Lectures: 11:00 am – 12:15 pm, TuTh, Broida 1640

Discussion Section: F 2:00 pm - 2:50 pm, Phelps 1260

TA:
Hyejin Ju
ju(at)physics.ucsb.edu
Office Hours: TBA  Office hours will be in the Physics Study Room.

Faculty Assistant: Ramces Jimenez
Office: Broida Hall 5114
(805) 893-3888
ramces(at)physics.ucsb.edu
Hours: 9:00 am - 12:00 noon, 1:00 pm - 4:00 pm, M-F

Required Textbook: David J. Griffiths, Introduction to Electrodynamics, 3rd edition. Same as for 110A.

The books by Wangsness, Marion & Heald, and Lorrain, Corson & Lorrain, and Jackson are on reserve in the Reserve Book Room of the Library.

Magnetism and Induction: We will begin with static magnetic fields: the Lorentz Force Law, Ampere's Law, and the Biot-Savart Law.  We will explore the vector potential and other problem-solving techniques. Next we will study magnetization and magnetic materials: bound currents, boundary conditions, and linear and nonlinear media.  We will then move to Faraday's Law, induced E-field, and inductors.  This leads to the displacement current and the full set of Maxwell's Equations.  We will finish with conservation laws for E and B fields.

The course will focus on solving problems.  Many of the problem-solving techniques are similar to those in electrostatics.  Superposition and symmetry remain critical.  Planar, spherical, and cylindrical geometries are fundamental. However, the sources of magnetic fields are vectors (currents or moving charges); rather than scalars (stationary charges), as for electrostatics.  We will make use of solutions for Laplace's equation and multipoles, although the peculiarities of magnetic fields require us to use them in new ways. 

Tests and Grading: I tentatively plan 2 midterms, each counting for 15% of the grade. Homework will count for 25%. The final will count for 45%. Exams and homework will be graded according to a curve. Typically, a grade of 93% or higher is an A, and 50% is on the dividing line between C and C-.  See the policy on late or missing homework or exams.

How to do Well in the Class:  Build your physics skills through deliberate practice:

Homework: Homework will be assigned each week, to be turned in by 5 pm on Monday in the box just outside the Physics Study Room, 1019 Broida. Assignments will include a few problems from the text and a couple of problems from elsewhere.  Solutions for the problems in the text will be posted on on eres.  Griffiths is a popular text, and solutions to the problems can be found online! Remember that thinking hard about problems, rather than simply looking up the solution, is an important part of learning to do physics.

Approximate Schedule of Lectures and Reading: (Subject to Revision)

Wk
 Date
 Reading
Topic
0
Review Ch 1-4

1
 6 Jan
 5.1
 Magnetostatics
 Biot-Savart Law

8 Jan
 5.2
Lorentz Force Law, Currents, Force on a Current
2
 13 Jan
 5.3
Continuity, Divergence and Curl of B, Vector Potential

15 Jan

Work by B, Ampere's Law
3
 20 Jan
 5.4
Vector Potential A

22 Jan

Rotating Charged Sphere, Multipole Expansion of A, Magnetic Scalar Potential
4
 27 Jan
 6.1
 Magnetic Fields in Matter Magnetization M, Ampere Construction, Bound Currents

29 Jan
Midterm Exam
5
 3 Feb
 6.2
Atomic and Electronic Magnetization

5 Feb
 6.3
Linear Media, Boundary Conditions
6
 10 Feb
 6.4
Paramagnetism, Diamagnetism, Ferromagnetism

12 Feb
 7.1 Electrodynamics Motional emf, Ohm's Law, Power
7
 17 Feb
 7.2
Faraday's Law, Mutual Inductance

19 Feb

Self-Inductance
8
 24 Feb

Inductors, Energy in B

26 Feb
 7.3
Displacement Current, Maxwell's Equations
9
 3 Mar
Midterm Exam

5 Mar
 8.1 Conservation Laws Poynting Vector, Conservation of Energy
10
 10 Mar
 8.2
Maxwell Stress Tensor

11 Mar

Angular Momentum, Review
Final Exam: Thursday, 19 Mar, 12 noon to 3 pm, in 1640 Broida

Homework Assignments (due Mondays at 5 pm in the box in the Physics Study Center).  Solutions are posted on eres.

N

Problems (from Griffiths unless given in full)

Due Date

1

 5.1, 5.3, 5.4, 5.8, 5.9, 5.10, 5.11

12 Jan

2

5.5, 5.13, 5.14, 5.15, 5.18, 5.38, and Additional Problems

20 Jan

3

5.24, 5.25, 5.33, 5.35, 5.39, and Additional Problems

26 Jan

4

1.60e (only pt e), 1.61, 5.37, 5.49, 5.60, 6.8, 6.10, and Additional Problems

2 Feb

5

6.1, 6.9, 6.13, 6.16, 6.17 and Additional Problems

9 Feb

6

5.23, 6.2, 6.14, 6.20, 7.1, 7.3 and Additional Problem

16 Feb

7

7.2, 7.6, 7.7, 7.10, 7.12, 7.15, 7.17 and Additional Problem

23 Feb

8

 7.21, 7.22, 7.27, 7.32, 7.36, 7.53 and Additional Problems

2 Mar

9

5.26, 6.28, 8.1, 8.2, 8.4 and Additional Problems

9 Mar

X

6.12, 7.28, 8.5, 8.6 and Additional Problems

Not graded