FORUM ON EDUCATION
Physics in Motion: A course for non-majors at Vassar College
Video analysis technology has been available for about two decades. I have incorporated in my introductory courses since 1995, initially with analog film and finally moving to digital video in the past five years. Since then, many innovative physics teachers have integrated video analysis into their introductory courses. This has been done to varying degrees, both at the high school and college level, in small liberal arts schools, community colleges and large universities. All of these uses were for courses where the majority of the students were representative of the usual population (pre-med, engineers, science majors, physics majors). Three years ago, I submitted a proposal to the National Science Foundation Course Curriculum and Laboratory Improvement (CCLI) Program. I wanted to develop and teach a course using the technique of video analysis, for a different student population and outside of the confines of the expected curriculum of an introductory physics course. The course, “Physics in Motion” is designed for freshmen in their first semester or for upper level students NOT majoring in the sciences. Taking video analysis outside of the standard curriculum has provided much more freedom in the topics covered and the order in which they are covered. Students have been “figuring out the physics” from the digital video with a little help and guidance from me.
During the first six or seven weeks of the course, they worked on projects (in groups of 2–4 students) investigating the concepts of velocity, acceleration, forces (including friction) and energy. For the first assignment, they filmed something (of their choice) that was slowing down. They predicted graphs of position, velocity and acceleration. After making the predictions, they analyzed their video on the computer using VideoPoint? and compared their predictions to the actual results. More important than correct predictions was their understanding of the differences between their predictions and the actual results. Students then worked in groups, sharing their videos and finding commonality. Whether the movie was of a ball thrown up or a teddy bear sliding on the dorm floor, the students were able to identify similarities and differences. Many of the activities in the first half of the course were in this form: look around for something that moves in a certain way, make predictions about its motion, film it, analyze it, compare and contrast, reconcile differences, share with others, make a movie or presentation to share with the whole class. Investigations included answering questions such as “ Does the coefficient of friction between two surfaces depend on the mass of the sliding object?” “How much smaller is the coefficient of friction on an air hockey table with the air on than with the air off?” and “Does the mass of an object affects how far it will slide before stopping on a surface with friction?”
In many of the presentations, I heard physics discussed in ways that I have never heard before in my “standard” introductory courses. The students seemed to get a much deeper understanding of the physics involved and were able to apply it to new situations with success.
The second half of the course was primarily devoted to the design, implementation and creation of a multimedia project for K-12 students. I could not have imagined all of the ideas that the groups (nine so far) thought of. DVD’s were created on playground physics, videogame physics, roller coasters, swimming and diving to name a few. They were presented in classrooms and auditoriums to students in 5th, 6th, 7th and 12th grades.
The Playground Physics project was created by three freshmen, all of whom had some physics background from high school but no multimedia experience. They went to the school and interacted with seven fifth graders chosen by the teachers to participate in the project. They interviewed the children and videotaped them on the playground. They asked the kids how fast they thought they could run, 1 mile an hour, 5 miles an hour or 10 miles an hour. Most of them said they could run about 1 mile an hour. They then taped the children running and analyzed the video to find that the average running speed was about 11 mph. Boy were they surprised! The project was then put together on DVD and presented in the auditorium of the elementary school for about 100 fifth graders, their teachers and the principal. The students stopped the DVD between sections and interacted with the kids, asking questions and elaborating on the concepts, which included gravity and free fall, running speeds and friction. After the presentation, the fifth graders were asked if they would like to study more about physics in the future. Eighty three percent said they would definitely be interested in learning more about physics!
Another excellent project was The Physics of Videogames done by three seniors in the course. They were majoring in Film, American Culture and English. They went to a local middle school and showed videogame clips to a sixth grade class. They interacted with the class, asking questions and having the students attempt some “videogame moves”. They came back three weeks later and presented the final DVD to the class. The main focus was on what is and isn’t realistic in a videogame. For example, in many videogames, the characters on the screen move one way in the air and then just turn around and go the other way. That violates the laws of physics! The point of the presentation was not to show that video games were bad, but to instill in the students the ability to discern what wouldn’t happen in reality. But that was okay because some of the games wouldn’t be nearly as fun if they stuck to all the laws of physics. Some students concluded they would love to study physics in the future because “its all about videogames”. Not true, of course, but if that’s the hook to get them to take physics in high school, who am I to argue. The teacher for this class had read about the projects from the prior semester in the local newspaper and had called me to see if we would come to her class. Afterward, she praised the presentations (interesting, relevant and fun), the interactions of the Vassar students with her students and the new insights she received about topics she teaches in her science class. She can’t wait for us to come back again!
When I originally designed the course I had assumed that the majority of the students enrolled would NOT have had high school physics. In the first class of sixteen freshmen, all but 4 had taken high school physics. This presented an immediate challenge in the course, and an adjustment in the material covered. Despite their high school physics background, the majority of the students learned more especially in the category of real world physics. The feedback from the Vassar students indicates that this is a useful and interesting addition to our curriculum. More important in my opinion is the interaction it has afforded myself and Vassar students with the local students and their teachers. In the first year alone, we gave physics presentations to over 300 students, 13 teachers, 2 principals and 2 district math/science directors. All of the feedback questionnaires given to both students and professionals indicate that the program was successful.
There of course have been many challenges and adjustments in the first year of teaching and developing this course. I love technology and computers when they work, but getting the students familiar with the computers, cameras and software was a major, time intensive challenge. It seemed like someone always had a problem right in the middle of my also trying to go over the physics. I highly recommend that others do this type of course but make sure that you have institutional support and a good student assistant!
Cindy Schwarz is an Associate Professor of Physics at Vassar College. She is the author of several books for the general public - A Tour of the Subatomic Zoo and Tales from the Subatomic Zoo. (http://faculty.vassar.edu/schwarz/)