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Fulvio Melia's Electrodynamics. My graduate course on E&M used this text as a basis for the lectures (subsequently changed to the aforementioned Jackson). This book is very short (246 pages as compared to say Griffiths at 624 pages!), but covers all the relevant topics of E&M (Electrostatics, Magnetostatics, etc) before smoothly transitioning into ...


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W. K. H. Panofsky and M. Phillips, Classical electricity and magnetism, Addison Wesley, 2nd ed., 1962 Especially the first 14 chapters are very enjoyable yet carefully written study text about both basic and more advanced topics in macroscopic EM theory (including discussion of EM energy from more experimental angle than is usual and of density of force ...


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Here is one suggestion: Assuming that spacetime is star-shaped around the origin $x=0$, define the interaction Lagrangian as $$L_{\rm int}(\tau)~:=~ x^{\mu}(\tau)~ \dot{x}^{\nu}(\tau)\int_0^1\! d\alpha~\alpha~ F_{\mu\nu}(\alpha x(\tau)) $$ $$ ~=~ \int_0^1\! d\alpha~\alpha~ x^{\mu}(\tau)~ \partial_{\mu}A_{\nu}(\alpha x(\tau))~ \dot{x}^{\nu}(\tau) ...


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Besides Purcell I really like Feynman Vol. II. I finally could understand magnetic materials and electromagnets. (Warning, Feynman uses his own notation for B,H and M.) The lectures are available online and for free, as the New Millenium Edition, at http://www.feynmanlectures.caltech.edu/, in a nice re-mastered edition with re-drawn ...


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Purcell is a good non-Griffiths option. I would judge the completeness of the material between Griffiths and Jackson, but with an intuitive level of understanding close to Griffiths. I used it to study for graduate qual exams when Jackson was making me feel particularly obtuse. Some positives: Touches more ideas than Griffiths Uses some real-world ...


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D.J. Griffith's Introduction to Electrodynamics must be mentioned. To my knowledge this text is ubiquitous in junior-level E&M courses. The writing is extremely friendly and is excellent for self-study. The author frequently tells you what he is doing and provides motivation, unlike the ubiquitous graduate-level text by Jackson. Equations often use a ...


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Jackson's classical electrodynamics is very complete, and often seen as the reference on CED. But I also like Rohrlich's classical charged particles that, as the title suggests, puts more emphasis on the subject of particles interacting with EM fields.


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I won't try to defend Feynman's derivation, which seems strangely non-relativistic. (A similar argument is used by Schwartz in his "Principles of Electro-Dynamics".) However, I will defend the result (the Lienard-Wiechert potentials), and specifically claim that they are not in conflict with your discrete charge example, at least for the case of uniform ...


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The geometry is not the same, they are complementary. The case where $\beta \approx0$ describes a very deep corner, so the space not occupied by the conductor is very narrow. The case where $\beta \approx 2 \pi$ is the case where the conductor is almost a thin sheet, that is, the space occupied by the conductor is very narrow. As expected, the charge ...


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Yes, optical activity can be affected by external electric and magnetic fields. Check out the Faraday effect: https://en.wikipedia.org/wiki/Faraday_effect Explanation of this phenomenon can be attempted with the assumption that the external magnetic field changes the electronic motion inside the molecules in such a way as to modify their effect on the ...


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The answer to the main question is YES. Two electrons will "touch" each other when their centers are at a separation equal to one electron diameter. Since the diameter of an electron is not zero, an infinite amount of energy, is not required to make them "touch." With a (calculated) electron diameter = to $2.82 \times 10^{-15}$ m, the required energy can be ...


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In this answer, I'll start with a real expression for $E$, because I think the exposition is clearer. There is no loss of generality in doing that, because the real expression will always be equivalent to the real part of the complex version of $E$, for some appropriate choice of the origin. Thus, my starting point is $$E(z,t)=E_0\ sin(k z-\omega t)\ .$$ ...


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Let's take a slightly more general case: Consider a wave with wave vector $\vec k=(k_x,k_y,k_z)$, with the electric field given by $$\vec E=\vec E_0\ e^{i(\vec k \cdot \vec r-\omega t)} $$ where $\vec r=(x,y,z)$. Now, we wan't to satisfy Maxwell's equations in the vacuum, including Gauss' law: $$\vec \nabla \cdot \vec E=0$$ The derivative is quite easily ...


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I don't think the increase in potential due to the moving charge leading to an "overcounting" IS in disagreement with Feynman's result. In fact, the "overcounting" is what leads to the 1/(1-v/c) enhancement factor in the potential equation precisely accounts for the fact that the slow moving charge has some of it's charge contributions "overcounted" because ...


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The following passage has been extracted from Bohr's Nobel lecture: While in contradiction to the classical electromagnetic theory no radiation takes place from the atom in the stationary states themselves, a process of transition between stationary states can be accompanied by the emission of electromagnetic radiation, which will have the same ...


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You are missing nothing. The Bohr model of the atom is false, and nowadays we replace the idea of the semi-classical "orbit" of Bohr with the fully quantum mechanical notion of orbitals or electron clouds, which give a probability distribution for the position of the electron around the nucleus, but do emphatically not imply that the electron is moving in ...



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