This preview shows pages 1–2. Sign up to view the full content.
Final Exam: Graduate Electromagnetics II, 95.658
Spring 2011, UMass Lowell, Dr. Baird
Part I: Multiple Choice (45 Points)
Circle the one best answer to each question.
1. At very high velocities, what role does a particle's rest mass play in its total energy?
(a) its rest mass becomes negligible
(b) its total energy is still directly proportional to its rest mass
(c) its rest mass becomes zero
(d) its rest mass is almost completely converted to radiant energy
2. Consider a perfect electric dipole that oscillates such that it emits electromagnetic radiation. In the
radiation zone, what is the polarization of the electromagnetic waves emitted?
(a) unpolarized
(b) circularly polarized
(c)
linearly polarized parallel to the dipole vector
(d) linearly polarized perpendicular to the dipole vector
3. What is the best statement summarizing the effect on an object's length due to frame motion in
Einstein's relativity?
(a) Rulers always measure the same no matter how they are moving
(b) A moving ruler is shorter in its own frame
(c) A moving ruler is seen by the stationary observer to be shorter than at rest
(d) A moving ruler is seen by the stationary observer to be longer than at rest
4. In the process of deriving radiation expressions from Maxwell's equations, how do we solve the non
homogenous wave equation?
(a) Place the sources inside a grounded spherical shell and apply boundary conditions
(b) Assume that far away all sources look spherical and sum over spherical harmonics
(c) Laplace transform the nonhomogenous wave equation
(d) Find and use the timedependent freespace Green function
5. What is the time averaged value of the energy flux of a traveling sinusoidal electromagnetic wave?
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview. Sign up
to
access the rest of the document.
This note was uploaded on 02/13/2012 for the course PHYSICS 95.658 taught by Professor Staff during the Spring '11 term at UMass Lowell.
 Spring '11
 Staff
 Mass

Click to edit the document details