PHYSICS 110A
ELECTROMAGNETISM
Fall Quarter 2009
Announcements:
Pratice Midterm 2: Unfortunately the lack of resources for UC has reduced the graders and TAs available so that a second midterm in the class is not feasible. However, please do this practice midterm to assess your skills in using orthogonal functions.
Solution to HW7, Problem 2: Download here!
Lecture Notes: For 9 Nov ("Conducting Sphere") and 13 Nov ("Multipoles") are now on eres.
Multipoles including φ-dependence: Jackson discusses general multipoles, including arbitrary dependence on φ, in Sec 4.1 at the beginning of Chapter 4. His qlm's correspond to my bl's. He uses Φ for the scalar potential (our V).
Geoid: The discussion on wikipedia is good. The GRACE satellite is now mapping the geoid, and has an excellent website.
Midterm: Is now graded and will be returned in class Friday, 30 Nov. For reasons that will be explained in class, the test was graded out of 110 points (33+33+44). (Of course, it will still count just 10% of your course grade, so the scale doesn't really matter.) The mean was 68 and the median was 72. The highest score was 110 (=perfect). This is just 10% of your grade, so: This doesn't determine your grade; but it hints what you must do to get the grade you want! It's a peek into the crystal ball.
Mathematica Spreadsheets for Lecture on 28 Oct: If you want to try these in Mathematica, save the (apparently incomprehensible) mathematica files to your desktop. Then open those files from inside mathematica. pdf versions of the notebooks are on eres.
sine wave & exponential
approximations to a square wave
Homework 4: Will be due on Tuesday, 3 Nov. I will assign a couple more problems for HW5, due the same day.
Midterm 1 Solutions: Are now on eres.
Atmospheric Electric Field, Thunderstorms and the Solar Cycle: You can read about this more in The global atmospheric electric circuit, solar activity and climate change by Rycroft, Israelson, and Price, J. Atmospheric and Terrstrial Physics (2000), 62, 1563. This link may not work off-campus -- it requires a journal subscription.
Point Charge in a Conductor: Those who would like to understand this problem in more detail might start with these notes. A great deal of literature deals with this problem; I came across it in plasma physics (see the book by F. Chen, on reserve in the library), but it also comes up in chemistry, and in semiconductor physics. "Debye shielding" is a generic term for the physics of the neutralizing electron cloud around a stationary charge.
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, F 2:00 pm - 3:00 pm
Discussion Section: F 10:00 am - 10:50 am, Phelps 3515
TAs:
Ju Hyejin
ju(at)physics.ucsb.edu
Office Hours: 2:00 - 4:00 pm Tues, 3:00-4:00 pm Weds. Office hours will be in the Physics Study Room.
Required Textbook: David
J. Griffiths,
Introduction
to
Electrodynamics,
3rd
edition. This book has become nearly
standard for
advanced undergraduate electromagnetism classes, worldwide.
Other books at about
the same
level are those by Wangsness, Marion & Heald, and Lorrain, Corson
&
Lorrain. Electrodynamics, by Jackson, is the standard graduate text.
These are
on reserve in the Reserve Book Room of the Library.
Electrostatics: Electromagnetism is the
original field
theory. Field theories have become one of the most powerful tools
of
physics. In this quarter we will study
electric fields that are static in time,
the subject known as electrostatics. Most of the forces that hold
together objects bigger than nuclei and smaller than planets are
electrostatic. Electrostatic forces are the basis of much of
solid-state electronics.
The course will focus
on solving problems. We will rely
heavily on the symmetries and properties of the electric field, but
will cover techniques with applicability to less symmetric problems,
and to problems throughout electromagnetism.
Tests and Grading: We will have one midterm,
counting for 10% of the grade. Homework will count for 34%. The
final
will count for 56%. Exams and homework will be gradedaccording to a
curve. See the policy on late or missing
homework or exams.
How to do Well in
the Class:
Build
your
physics
skills
through
"deliberate
practice":
- Do the reading
- Attend lecture and discussion section
- Take notes and ask questions in class or discussion section
- Do the homework and hand it in on time, then look at solutions
- Study your notes and homework before exams
Homework: Homework will be assigned each week, to be
turned in
by 5 pm on Tuesdays 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 |
|
|
25 Sep |
Giffiths 2.1 |
Electrostatics |
Coulomb's Law, E-Field, Superposition |
|
1 |
28 Sep |
2.2 |
|
E-Field Lines, Gauss's Law |
|
|
30 Sep |
|
|
Divergence of E, Curl of E |
|
|
2 Oct |
2.3 |
|
Electric Potential V |
|
2 |
5 Oct |
|
|
Poisson's and Laplace's Equations |
|
|
7 Oct |
|
|
Examples |
|
|
9 Oct |
|
|
Boundary Conditions at Surfaces |
|
3 |
12 Oct |
2.4 |
|
Energy in Charge, V, or E |
|
|
14 Oct |
2.5 |
|
|
|
|
16 Oct |
|
|
Capacitors |
|
4 |
19 Oct |
3.1 |
Special Techniques |
Existence and Uniqueness |
|
|
21 Oct |
|
|
Review |
|
|
23 Oct |
Midterm 1
|
||
|
5 |
26 Oct |
3.2 |
|
Method of Images |
|
|
28 Oct |
3.3 |
|
|
|
|
30 Oct |
|
|
Examples |
|
6 |
2 Nov |
|
Orthogonal Series: Spherical |
|
|
|
4 Nov |
|
Spherical Series |
|
|
|
6 Nov |
|
Spherical Series |
|
|
7 |
9 Nov |
|
Multipoles |
|
|
|
11 Nov |
Veteran’s Day Holiday |
||
|
|
13 Nov |
|
|
Multipoles |
|
8 |
16 Nov |
4.1 |
|
Electric Polarization of Atoms and Molecules |
|
|
18 Nov |
|
|
Polarized Molecules in Matter |
|
|
20 Nov |
4.2 |
|
Bound Charge |
|
9 |
23 Nov |
|
|
E-Field Inside a Polarized Material |
|
|
25 Nov |
4.3 |
|
Electric Displacement D |
|
|
27 Nov |
Thanksgiving Holiday |
||
|
10 |
30 Nov |
4.3 |
|
Boundary Conditions at Surfaces |
|
|
2 Dec |
4.4 |
|
Linear Dielectrics |
|
|
4 Dec |
|
|
Energy in Dielectrics |
|
Final Exam: Thursday, 10 Dec,
4-7 pm, in
3515 Phelps |
||||
Homework
Assignments (due Tuesdays 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 |
2.2, 2.5, 2.7, 2.12, 2.16 and HW1 |
6 Oct |
|
2 |
2.21, 2.22, 2.26, 2.29, 2.30 and HW2 |
13 Oct |
|
3 |
2.32, 2.36, 2.37, 2.39, 2.46 and HW3 |
20 Oct |
|
4 |
3.1, 3.3, 3.6, 3.10 and HW4 |
6
Nov, 3 pm |
|
5 |
6
Nov, 3pm |
|
|
6 |
3.18, 3.20, 3.21, 3.24 HW6 |
13
Nov, 3 pm |
|
7 |
3.28, 3.33, 4.1, 4.5 HW7 |
20 Nov |
|
8 |
1 Dec |
|
|
X |
Not graded |