PHYS4210 Quiz: Electromagnetic Theory - Prof. James J. Napolitano, Quizzes of Physics

Download PHYS4210 Quiz: Electromagnetic Theory - Prof. James J. Napolitano and more Quizzes Physics in PDF only on Docsity! Name: PHYS4210 Electromagnetic Theory Quiz 26 April 2010 This is a closed book quiz! Write the best choice in the space next to the question. 1. Which of the following is not true about the radiation fields from a moving charge? A. The radiation is in the direction E×B. B. E and B are perpendicular to each other. C. Radiation occurs even for nonrelativistic velocities. D. They only arise from charges with nonzero acceleration. E. They are inversely proportional to the square of the source distance. 2. An electromagnetic wave propagates in the z-direction with E(t,x) = E0e −i(ωt−kz). For a circularly polarized wave, E0 would be proportional to A. x̂ B. ŷ C. ẑ D. x̂ + ŷ E. x̂ + iŷ 3. A charge moves through a dielectric medium with speed v. If n is the index of refraction of the medium, which of the following is the necessary condition if the charge is to emit Čerenkov radiation? A. v < c B. v < nc C. v < c/n D. v > c/n E. v > c/n2