Performance-Based Assessments for Network Analysis Competencies

The purpose of this exercise is for students to use simultaneous equations to arrive at values for fixed resistors R₁ and R₂ that will limit output voltage adjustment to the limits specified.

An extension of this exercise is to incorporate troubleshooting questions. Whether using this exercise as a performance assessment or simply as a concept-building lab, you might want to follow up your students’ results by asking them to predict the consequences of certain circuit faults.

Use a variable-voltage, regulated power supply for V_thevenin, and a fixed-voltage supply for V_source. Specify standard resistor values, all between 1 kΩ and 100 kΩ (1k5, 2k2, 2k7, 3k3, 4k7, 5k1, 6k8, 10k, 22k, 33k, 39k 47k, 68k, etc.) for resistors in the original circuit. A decade box or potentiometer will suffice for R_thevenin.

In case it is not already crystal-clear, I want students to build two different circuits for this exercise: the “original” circuit and also a “Thevenin equivalent” circuit, then plug the exact same load resistor into both circuits (one at a time) to see that the voltage across it is the same in both cases. Many students seem to struggle with the basic concept of equivalent circuits, and I have found this exercise (once successfully completed) to be excellent for “making it real” to these students.

An extension of this exercise is to incorporate troubleshooting questions. Whether using this exercise as a performance assessment or simply as a concept-building lab, you might want to follow up your students’ results by asking them to predict the consequences of certain circuit faults.

Use a variable-voltage, regulated power supply for V_thevenin, and a fixed-voltage supply for V_source. Specify standard resistor values, all between 1 kΩ and 100 kΩ (1k5, 2k2, 2k7, 3k3, 4k7, 5k1, 6k8, 10k, 22k, 33k, 39k 47k, 68k, etc.) for resistors in the original circuit. A decade box or potentiometer will suffice for R_thevenin.

In case it is not already crystal-clear, I want students to build two different circuits for this exercise: the “original” circuit and also a “Thevenin equivalent” circuit, then plug the exact same load resistor into both circuits (one at a time) to see that the voltage across it is the same in both cases. Many students seem to struggle with the basic concept of equivalent circuits, and I have found this exercise (once successfully completed) to be excellent for “making it real” to these students.

An extension of this exercise is to incorporate troubleshooting questions. Whether using this exercise as a performance assessment or simply as a concept-building lab, you might want to follow up your students’ results by asking them to predict the consequences of certain circuit faults.