PHYS 100C

Revision as of 18:34, 1 May 2013

RECENT UPDATES:

• April 23: Lecture 7 (PDF) Summary: we introduced gauge transformations (10.1.2), Coulomb and Lorentz gauges, and Maxwell equations in these gauges (10.1.3). Introduced "retarded" potentials in Lorentz gauge and demonstrated that they are a solution to Maxwell equations for potential V(r,t) (10.2.1).

• April 22: Group vs. phase velocity animation.

• April 22: The Homework grades are posted here: GoogleDrive

• April 20: Lecture 6 (PDF) covered waveguides.

• April 16 Lecture 5 (Tuesday) will be delivered by Prof. Sunil Sinha (I am out of town). I will be back for Thursday April 18 (Homework #2 is due on Thursday).

Lecture 5 (PDF) summary: we considered a simple mass-on-a-spring model for electron driven by electromagnetic wave to calculate dependence of index of refraction and attenuation as a function of frequency, leading to dispersion (rainbows etc.) We started deriving propagation of EM waves in a hollow metallic waveguide.

• April 11: Lecture 4 (PDF) Summary (with a tilda): we considered E&M waves propagating in conducting materials. Wavevector k becomes complex, with imaginary part of k representing exponential attenuation of the wave (skin depth introduced). E&M are still transverse but no longer in phase. Re-deriving the boundary conditions (Lecture 2/3 with complex k) get 100% reflection - explains why metal objects/mirrors are shiny. The physics explanation is that the surface currents "conspire" to screen out the EM fields from entering the bulk of the metal - the superposition of the incident fields and these currents produces all the new effects: out of phase E, B; rapidly decaying fields as a function of distance from the interface, and strongly reflecting surface, as a result.

• April 9: Lecture 3 (PDF) summary: we considered boundary conditions for a plane EM wave incident on an interface at arbitrary incident angle. We have derived three laws of reflection/refraction and derived Fresnel Law for p-wave.

(p stands for parallel, s stands for senkrecht, German word for "perpendicular" - to the plane of incidence). We have considered Brewster angle physics which included polarized sunglasses and Brewster Angle Microscopy.

• Historic Perspective (not required, but could be of interest for those of you who like the history of science): the fact that light is E&M wave was *almost* derived by Wilhelm Eduard Weber and Rudolf Kohlrausch in 1856. Maxwell made the connection in 1861.

Einstein wrote about this prediction:Of Maxwell's work:

"Imagine [Maxwell's] feelings when the differential equations he had formulated proved to him that electromagnetic fields spread in the form of polarised waves, and at the speed of light! To few men in the world has such an experience been vouchsafed... it took physicists some decades to grasp the full significance of Maxwell's discovery, so bold was the leap that his genius forced upon the conceptions of his fellow-workers."

Maxwell's conjecture was proven by Hertz in 1887, who was only 4 years old in 1861, when Maxwell first postulated that light is Electromagnetic Wave.

• April 4: Lecture 2 (PDF) summary: we considered energy and pressure carried by radiation / EM wave. We have looked at propagation of waves in media; We started derving the properies of transmitted and reflected wave equations for a plane EM wave normal-incident at the boundary between two media (using boundary conditions from Eq. 7.64) - we stopped half-way through derivation though, will pick up the calculation next Tuesday in class!

April 2: Lecture 1 (PDF) summary: we covered waves in 1D (9.1.1-9.1.2), discussed transverse/longitudinal waves (9.1.4), derived EM waves in vacuum from Maxwell Eqs. (9.2.1, 9.2.2).

COURSE SUMMARY:

PHYS 100C, Electromagnetism, Spring 2013, UC San Diego

Professor: Oleg Shpyrko, oleg@physics.ucsd.edu

Office: Mayer Hall 3210, ext. 4-3066 (Where is it?)

Office Hours: Mondays 4-5PM as well as Discussion Session on Friday, 2PM-2:50PM, YORK 4080A

TA (Grader): Leandra Boucheron, lboucheron@gmail.com

Text: Introduction to Electrodynamics, 3rd Edition, by David J. Griffiths. (also check abebooks for used copies)

Lectures: Tue, Thu, 11:00AM-12:20PM, SOLIS 110

Discussion Session: Fridays, 2-2:50PM, YORK 4080A

Homework: Assigned weekly, due Thursdays, at the START of lecture. Will also be accepted at the following Tue lecture, but with a 20% penalty.

Midterm: May 7th 11AM (in class). Open book exam. Bring your textbook only, and a bluebook.

Final: TBD. Open book exam. Bring your textbook, notes, and a bluebook.

Grading: Homework=20%, Midterm =30%, Final=50%.

Academic Dishonesty: Please read the section entitled "UCSD Policy on Integrity of Scholarship" located in the2008-2009 General Catalog, www.ucsd.edu/catalog. The rules on academic dishonesty will be strictly enforced!

Course Webpage: x-ray.ucsd.edu/PHYS_100C (RSS/Atom feeds available) ---

COURSE SCHEDULE: