A six-second video that helps to explain the mechanics of waves, longitudinal and traverse, reaches nearly 300,000 views on a professor’s YouTube channel. Students from all over the world leave positive comments after viewing the video, including, “A six-second video that would have saved three physics classes.”
Sitting in a plenary of the Central Pennsylvania Section of the American Association of Physics Teachers on the topic of gravity and orbits, he looks up to see one of his video animations used to help explain a concept. It’s a good feeling.
It all began in the early ‘90s for Michael Gallis, associate professor of physics at Penn State Schuylkill, with simple animated GIFs. Self-taught and resourceful, he uses an open source license and a free software program, POV-Ray, to generate single frames of animations, which he then sews together into a video. Often these type of videos are generated by an entire team of graphic designers and animators for large companies, not one professor.
“When I created my early videos, they were simple designs that were made to repeat and fit on a floppy disc,” said Gallis with a sly smile, knowing that many reading this, including his students, would not be familiar with the term ‘floppy disk.’ “As computer screens became higher in resolution, I switched to AVI and later to an MP4 format that permitted browsers to automatically play the video when opened. I also added narration.”
Although Gallis spends a good deal of time in the classroom and in the community with myriad outreach activities, a pivotal space for him is the Internet. He has created nearly 300 animations, including interactive visualizations that have garnered more than 4 million views.
“The impetus for many of the videos is to assist students in learning physics fundamentals that pose the most difficulty,” said Gallis. For example, an astronomy teacher provided feedback on the challenges of understanding an angle view -- an eclipse -- of the planets from above. “If you look at photo depictions at a certain angle, the rings looked squashed around the planets when, in fact, they are nearly perfectly circular from above,” he explained. With additional perspectives and panning facilitated by the video, the students gain a better understanding of the ring shapes.
Gallis said that some of the video animations are more complex and time consuming than others, including one of a roller coaster with miniature cars circling the tracks. “In this video, I wanted to use 3D animation and provide an external and first-person view with an emphasis on precise physics.” The video helps students understand how to calculate the horsepower required to maintain a constant speed or coast through a loop.
One of Gallis’ latest interactive videos tells a story of the drag impact but also of buoyancy using beach balls. He said that everyone thinks of the drag factor, but it is only a small part of the story. Accordingly, if you measure either an empty or a full (air) beach ball on a scale, you will achieve the same result. “The beach ball’s drag is only 60 percent of what should be. And then, there is also the Magnus effect,” Gallis explained. To illustrate the Magnus effect, he references a widely popular video on Youtube in which a basketball is thrown downward in a dam two times. “The basketball thrown straight down lands where you might expect it, but the one tossed with a backspin goes down and shoots out, it’s the same physics as with a curve ball,” he said.
Added to his repertoire of animations, interactive animations are novel experiments. Next fall, Gallis will collaborate with two of his colleagues in bringing a virtual world to Penn State Schuylkill students.
Beyond classroom instruction and educational video production, Gallis is a familiar face in local communities. Whether demonstrating his bicycle wheel or bed of nail experiments to local schools, libraries, the Girl Scouts and others, he is always making a positive impact. “I am avid about outreach and believe it is something every science teacher should do as a resource to the community,” he said.
In 2009, Penn State Outreach selected Gallis as the faculty lead for the Physics Asset Project.
Since 2004, he has participated in Open Source Physics (OSP), which has influenced his video creation and provided him with vital mentorship. OSP states on its website that “computers and computer-based instruction pervade our academic institutions, and much of experimental and theoretical physics cannot be done without the aid of computers.”