Microcomputer-Based Labs

at the University of Minnesota

Why change labs that already work?

"Even if you're on the right track, you'll get run over if you just sit there." -- Will Rogers.

The world around us is constantly changing. New technology, new ideas, new breakthroughs in education all lead us to a constant evaluation of the work we do in the physics department of the University of Minnesota. Our goal is to give our students the best possible education we can give them. This often means trying new things and seeing how best we can apply them to our situation.

Why use microcomputer based labs (MBLs)?

Computers are an increasing presence in all of our lives. Physics in particular is heavily dominated by technology, from high school classrooms to university research and industry labs. Students are starting to use computers in both primary and secondary classrooms. Many of the students in our introductory courses have used computers in their high school physics classes, and in other high school and college courses. The Third International Mathematics and Science Study found that 42% of high school physics students have been asked to use computers in their class. Since our 125x sequence students are primarily engineers, most of our students will move on to use computers both in their engineering courses and in the labs and research groups they work at. Early and frequent exposure to computers will help our students develop the familiarity with computers that they will need in their classes and in the workforce. We can support this process by using computers in our labs.

Computers also allow for a much greater range of data gathering and analysis than our traditional labs allow for. With computers, students can take cleaner data and spend less time on analysis, and more time on the concepts.

Try the following site for more discussion on this subject. Why use computers to teach Physics Labs?

What sort of research is there on computers in labs?

There is a growing body of research in this area. For a quick look at some of it, follow the links on our resources and references page. You can also find resources on this subject in the Journal of Computers in Mathematics and Science, or the Journal of Research on Computing in Education.

How have computers been implemented at the University of Minnesota?

Our computerized labs use the same cooperative group problem solving techniques that our traditional labs do. The lab problems are very similar, and the structure of the lab remains the same. The only difference is the manner in which students collect data and analyze it to solve the lab problem.

We chose to use a video capture and analysis system for data collection and analysis. Our labs are equipped with Macintosh PowerMacs, with audio-visual (AV) capabilities built in. Included with the Macs is a video capture program, Apple Video Player. Groups use this software with small security-type cameras to take movies of carts rolling on tracks, accelerating hanging masses, blocks sliding down ramps, and other motion-based phenomena. The movies are saved to the computer's hard disk in a folder specifically for that group's lab section.

Once the students have a movie that they are pleased with, they open up a software program called VideoTOOL, designed and built by the University of Minnesota Physics Education group and Ted Hodapp from Hamline University, using the LabVIEW environment.

VideoTOOL is graph-oriented, and does not do the analysis for the students. Instead, the software guides the students through several phases. First the students predict what the particular motion they are studying will look like on a graph, picking the proper equations and coefficients to match their prediction. Then the students open their movie from within VideoTOOL and calibrate the scale, choose axes, and set the time = 0 point. After the calibration is finished, students collect data by following the object on the screen with the mouse. Data is plotted as it is gathered. Once the data collection is over, students compare their prediction to the data, and fit the data with a new line, selecting an equation and coefficients as in the prediction. With the position data fit, students are asked to predict the shape of the velocity graph. Then the program analyzes the position data and plots the velocity data. Students then fit the velocity data, and then predict the acceleration. A similar process for acceleration gives the students six graphs; position, velocity, and acceleration in both the x and the y direction. The graphs are printed out for the students to review and use in their lab reports. The printouts include both predicted and fitted values for all six graphs.