• Obtain solutions to Laplace's and Poisson's equations for simple configurations of materials and sources.
• Determine the capacitance of simple practical systems of conductors
• Determine the self and mutual inductance of simple practical current carrying systems
• Apply the basic principles of electromagnetic motors and generators
• Determine the transmission of energy by low loss TEM transmission lines from a simple source to a passive load
• Determine the reflection and transmission of energy for uniform plane waves incident on planar material boundaries for low loss or conducting media

Class Schedule

The class schedule may be changed as the semester progresses, so check it regularly and note the revision date.

LMS (WebCT) Information

Class notes, copies of lecture slides, lecture quizzes and grade information are all available through the RPI LMS (formerly WebCT). To access any of these materials, you must begin by logging onto the ECSE-2100 Fields and Waves I from the Course List. The format used for the WebCT pages is still used so that accessing some information may be a little inefficient.

• Lecture Quizzes
  • Under the Course Tools Menu at the left, click on Assessments.
  • Lecture Quizzes and some Extra Credit are listed in reverse order. Go to the bottom of the list to find the quiz you are looking for.
  • Note the times that the quiz is available. Be sure you complete it before it closes.
  • The quizzes usually work well, but if you have problems and you think you are not getting credit for correct answers, then send your answers to Prof. Connor so he can check them. If you are correct, he can fix the grade to reflect that.
• Class Notes & Lecture Slides
  • Under the Course Tools Menu at the left, click on Course Content. When the page of icons appears, click on the one called Course Content (looks like a backpack)
  • Class Notes (essentially a complete book) are listed as items 1.1 through 1.14
  • Appendices to the Class Notes are listed as items 2.x
  • Lecture Slides are listed as items 3.1 through 3.25. Note that they are available in two forms - either one slide per page or six slides per page.
  • Extra Files, listed as items 4.x, contain information used on some Lecture Quizzes.
    

Extra Credit

During classtime for the last few meetings of the term, there will be extra credit exercises each day. In addition, there is an extra credit project (information on the Project Page) and there will be an extra set of WebCT questions (like the lecture quizzes) available after the third quiz. One difference in these questions is that you will have only one chance to answer each question. Also

Office Hours/Open Shop

From time-to-time, there will be extra open shop, usually for projects. Please contact the TAs or instructor by email for help most any time of day.

Comments on Projects

See Handouts page.

Comments on Homework

HW1: It is generally a good idea to complete as much of the assignment as you can outside of class. Classtime should be used to finish up assignments rather than doing them completely. This applies to all HW assignments.

HW4: There are quite a few examples of spreadsheet analysis posted online. Also, there is a write-up on using the spreadsheet that you can find on the supplementary materials page. Finally, there are some comments on this assignment and Lecture Quiz 13.

Note that in HW3, the relationship between the voltage between the inner and outer conductor and the charge on either conductor is found. It is not exactly in the form of Q=CV, but it is very close. It is not a lot of work to modify the expressions a little and then find C, as you are asked to do in problem 1.

For the numerical method, it does not really matter what values you choose for the electrode voltages, since you will be dividing them out anyway. The one exception is the outer shield, which should be kept grounded for this problem. You should look at some of the examples that have been posted -- there are several. See if you can set up one or two of the examples, which should help you see where all the info comes in. As for the dielectric constant, that should show up in the cells at the boundary between the dielectrics.

HW5: For the coaxial cable model of resistance, you must use the per unit length expression for the capacitance to get the per unit length expression for the conductance. Then, multiply the per unit length expression for the conductuance by the length of the line to get the full conductance and then invert it to get the resistance. You cannot invert the per unit length expression for conductance to get the per unit length expression for the resistance.

Be sure you use the radius and not the diameter in the resistance expressions.

To find the information on Lightning in the Green Book, check the Index of the document under Lightning and look for the information on typical current in strokes.

When you calculate the resistance of the grounding rod, be sure that you use SI units. The information in the Green Book is not given in SI units.

The answer to problem 4 should look like the signal you see when you do the experiment where you drop the magnet down the PVC and copper pipes. The flux calculation should be quite simple so if your expression is complicated, you are probably doing something wrong. Remember that you are evaluating the line integral of the vector potential around the loop of radius b so there is quite a bit of simplifying you should do before evaluating anything. To help visualize things a bit better, here is the geometry. Always remember to simplify things as much as possible before most math operations. Of course, be sure you don't over simplify.

HW6: Note that problem 2 has been changed to an RG-142 cable, because RG-58 cables rarely use Teflon now. Also, problem 4 has now been solved. You can still do the extra credit part if you wish, but you no longer have to work on the main problem. Using Matlab to find answers to questions is strongly encouraged. It is much simpler and more consistent to work out the method and then have Matlab figure out the numbers than to crank through everything separtely.

A hint on how to figure out the dimensions of the RG-142 cable ... you should be able to find the center conductor dimensions by looking online (Google RG142 center conductor) and then the formula for the capacitance should give you the ratio ln(b/a). You are basically reverse engineering the cable from published info and what you know about coaxial cables and transmission lines.

For the solution, essentially all of the work was done using Matlab. The solution for problem 3 (forces) was included in the m-file for problem 1, since it was the same configuration.

HW7: Parameters for seawater have been added to keep things simple. Note that the electrical properties of seawater depend quite strongly on temperature, salinity, etc. There is a good paper on this on the Supplementary Materials page.

This assignment (HW7) is now due at the beginning of lecture, Thursday, 17 April.

The most up-to-date reading list for the class notes.

The MathCAD Explorer and the Visual Electromagnetics Workbook we use in class can be downloaded from the web. Please see the bottom of the main Class Information Page under TEXT .

Almost any Spice based program can be used to model transmission lines, but we use the PSpice program available through Cadence/OrCAD. The most recent version is the version 10.5 OrCAD Demo, but there is an older and smaller version 9.1 PSpice Student that will do everything we need for this course. If you have not used PSpice for transmission line analysis previously, you may want to review the document posted on the Projects page on Designing with PSpice. There is a reasonably reliable work around that permits designs to be shared. First create the design and simulate it to be sure everything is working well. You will notice that this creates several files, one of which ends in the extension DSN. You can send this file to anyone else to share what you have done. To use the file, open it from whatever version of PSpice you are running. Don't try to run it, however. Rather copy the circuit diagram and paste it into a new project. The new project should now work. You will have to set up a simulation, but, otherwise you will have saved a lot of effort by not having to input all of the parts.

There are many links to useful software and other information in the lecture slides and in the Supplementary Materials Page.

Homework assignments are posted on the Handouts page.

PDF versions of most course handouts will be available on the Handouts page. (Accessible from home page ).

Quiz Grades and Other Grade Info

Grade Statistics for Quizzes and other assignments can be found on LMS (WebCT)

Quiz 1 -- approximate grade breakdown. A: 86-100 B: 73-86 C: 53-72 D: 43-52

Quiz 2 -- approximate grade breakdown. A: 90-100 B: 75-89 C: 60-75 D: 50-60
Note also that several students solved problems 6 and 7 in spherical coordinates rather than cylindrical. There is a penalty of 20% of the points earned for problems 6 and 7, so factor this in when determining your grade. The grades posted on LMS (WebCT) include this factor.

Quiz 3 -- approximate grade breakdown. A: 90-100 B: 80-89 C: 70-79 D: 55-69

Final Exam -- approximate grade breakdown. A:162-200 B:133-161 C:107-132 D:87-106 The final was one long problem too long and, thus, the median was lower than it should have been. Thus, the grades are curved.

Final Course Grades -- all grades are now posted on LMS and the final course grades are available through SIS.

If you wish your quiz to be regraded, please write a note on it explaining where you think you deserve more points and submit it to one of the course staff (instructor or TA). This should be done within two weeks of a quiz date.

Questions on Quiz 3 from other terms:

Spring 2007

1. Why is NI constant?  If you increase N doesn't the value increase? Ans: Recall that the energy in this case comes from the capacitor. Since the energy in the capacitor is fixed, the energy in the inductor is also fixed. The energy is proportional to LI² and L is proportional to N ² then (NI)² is fixed, which also means that NI is fixed.
2. Where does the value t = 3.5x10⁷ come from? Where does the value 0.085 come from? Ans: the first parameter is the conductivity of aluminum, which is included in the data table at the end of the quiz. The second parameter comes from plugging the numbers for permeability and conductivity into the expression for the skin dept. The only unknown is f, so that is all that is left in the expression, once everything else has been evaluated.
4. Does it matter which way the loop is oriented?  If the loop was in the counterclockwise direction would the answer be (b)? Ans: It does not matter what direction the loop is oriented, as long as the wire passes through it. Yes, the answer switches to b if the loop goes the other way. Mathematically it matters which way one integrates around the loop. Practically, it usually does not matter since we mostly care about the magnitude of the current.
6. Magnetic Field is B and magnetic field intensity is H? Ans: usually B is the magnetic field (it is actually the magnetic flux density) and H is the intensity.