Electromagnetics Concept Inventory Assessment Instruments

The goal is to develop assessment instruments to measure students' conceptual understanding of fundamental concepts in electromagnetics. Although primarily intended for junior-level electromagnetics courses in electrical engineering departments, the Electromagnetics Concept Inventory (EMCI) can also be used in a variety of undergraduate and graduate electromagnetics-related courses in engineering and physics departments. EMCI Version 1.0 is composed of three exams: EMCI-Fields, EMCI-Waves, and EMCI-Fields & Waves, to allow instructors to target specific knowledge areas.

The EMCI is motivated by the Force Concept Inventory created by Halloun and Hestenes[1–4] and its impact on physics education. The Force Concept Inventory (FCI) was designed to measure conceptual, not computational, understanding of Newtonian Mechanics. The questions are posed to focus on intuitive comprehension independent of knowledge of the terminology or numerical modeling. Following the lead of the FCI, faculty members are creating concept inventories for other disciplines. More information about concept inventories can be found in a paper by Evans and Hestenes.[5]

For more information or to obtain a copy of either version of the EMCI, please contact Branislav Notaros, Electrical and Computer Engineering Department, Colorado State University.

EMCI Package

The EMCI-Fields version 1.0 consists of 23 multiple-choice questions on electrostatic, magnetostatic, and time-varying electromagnetic fields. It is designed for a typical first-semester electromagnetics course in a two-semester sequence. The EMCI-Waves, consisting of 23 questions on uniform plane waves, transmission lines, waveguides, and antennas, is intended for a typical second-semester course in the two-semester sequence. The EMCI-Fields & Waves is an integral test with 25 questions on all basic topics in undergraduate electromagnetics. Instructors teaching a one-semester electromagnetics course may either use both the EMCI-F and EMCI-W (at the same time or at different points in the semester) or use the EMCI-F & W only. EE and physics faculty members may also use these exams as review tests in senior and graduate EM-related classes.

In addition to the copies of the three tests, the EMCI package includes detailed instructions, concept lists, and answer sheets. An instructor feedback form is also provided. It requests input from the instructor regarding the EMCI tests and how well they fit with the objectives, assessment processes, and pedagogical approaches used in the course. In addition, it solicits comments and suggestions for improvement of the instruments.

EMCI-Waves Concepts

The following list shows the concepts covered by the EMCI-Waves version 1.0.

  • Basic properties of uniform plane traveling waves (2)
  • Propagation in good conductors and good dielectrics (2)
  • Skin effect and electromagnetic shielding (1)
  • Properties of standing waves (4)
  • Wave reflection, transmission, and refraction at interfaces (3)
  • Wave polarization (1)
  • Considering objects in electrical dimensions (3)
  • Equivalent circuit model of a transmission line (2)
  • Energy localization and transfer in a transmission line (1)
  • Impedance transformation, matching, Smith chart (3)
  • Transients on a transmission line (3)
  • Rectangular waveguides and cavity resonators (3)
  • Far-field region of an antenna; antenna directivity and gain (3)
  • Short dipole, small loop, half-wave dipole, and quarter-wave monopole antennas (3)
  • Effective area of a receiving antenna; Poynting vector (1)
  • Friis transmission formula for a radio link (1)

EMCI Development Process

The EMCI Version 1.0 has been developed during the 2000-01 academic year and the summer of 2001. The tests are being administered in a pre- and post-test format in the Fall 2001 Electromagnetic Theory I and II courses at the University of Massachusetts Dartmouth. Post-exam interviews with students will be conducted. The tool has been shared with colleagues in other NSF Foundation Coalition institutions and other schools in the country.

EMCI-Fields Concepts

The list below shows the concepts covered by the EMCI-Fields version 1.0. The numbers in parentheses indicate how many questions in the current version of the exam address the outlined topics. Note that the numbers do not add to 23 because questions covering more than one concept are counted multiple times.

  • Coulomb's law and Gauss' law (2)
  • Adding vectors (forces and fields) in space; using symmetry (3)
  • Conservative field; electric potential (2)
  • Behavior of conductors in the electrostatic field (4)
  • Electrostatic induction, shielding, and image theory (3)
  • Boundary conditions for electrostatic fields (3)
  • Capacitors and capacitance (2)
  • Current continuity; boundary conditions for steady currents (2)
  • Magnetic forces and torques (2)
  • The Biot-Savart law and Ampere's law (3)
  • Law of conservation of magnetic flux; magnetic circuit (2)
  • Boundary conditions for the magnetostatic field (1)
  • Gradient, divergence, and curl (2)
  • Faraday's law of electromagnetic induction (3)
  • Inductance (1)
  • Displacement current and general Maxwell's equations (1)

References for further information

  1. Hestenes, David, Malcolm Wells, and Gregg Swackhamer, 1992. Force Concept Inventory. The Physics Teacher, 30 (3), 141–151.
  2. Hestenes, David, and Ibrahim Halloun, 1995. Interpreting the Force Concept Inventory. The Physics Teacher, 33 (8).
  3. Halloun, Ibrahim, and David Hestenes, 1985. The initial knowledge state of college physics students. American Journal of Physics, 53(11), 1043–1055.
  4. Halloun, Ibrahim, and David Hestenes, 1985. Common sense concepts about motion. American Journal of Physics, 53(11), 1056–1065.
  5. Evans, D.L., and David Hestenes, "The Concept of the Concept Inventory Assessment Instrument, Proceedings, 2001 Frontiers in Education Conference, Reno, Nevada, 10–13 October 2001.
  6. Notaros, B.M. (2002). “Concept Inventory Assessment Instruments for Electromagnetic Education,” Proceedings, IEEE Antennas and Propagation Society International Symposium, San Antonio, Texas
  7. Evans, D.L., Midkiff, C., Miller, R., Morgan, J., Krause, S., Martin, J., Notaros, B.M., Rancour, D., and Wage, K. (2002). “Tools for Assessing Conceptual Understanding in the Engineering Sciences,” Proceedings, Frontiers in Education Conference, Boston, USA
  8. Evans, D.L., Gray, G.L.., Krause, S.J., Martin, J.K.., Midkiff, C., Notaros, B.M., Pavelich, M., Rancour, D., Reed-Rhoads, T., Steif, P., Streveler, R., Wage, K.E. (2003). “Progress on Concept Inventory Assessment Tools,” Proceedings of the Frontiers in Education Conference.