The LivePhoto Physics Project team includes
  • Robert Teese (Rochester Institute of Technology)
  • Alicia Allbaugh (JPL NASA)
  • Patrick Cooney (Millersville University)
  • Priscilla Laws (Dickinson College)
  • E. F. (Joe) Redish (University of Maryland)
  • David Sokoloff (University of Oregon)
  • Ronald Thornton (Tufts University)
  • Maxine Willis (Dickinson College)

During the past fourteen years, we have led over 25 workshops to help college and high-school teachers learn how to use video analysis in introductory physics courses. A primary objective of the workshops was to make video analysis a hands-on activity for the students, which includes having the students make their own videos. The teachers in the workshops were eager to make and analyze their own videos in class, and to help their students to do the same, but most of them also wanted a source of ready-made videos to serve as examples and as backups for times when the instructors do not have time for making their own. The LivePhoto Physics project was created to help these workshop participants and other teachers obtain high-quality videos for use in one-year physics courses.

LivePhoto Physics Project Summary
The LivePhoto Physics project is developing a collection of digital video analysis materials for introductory physics courses, using research-based development methods that were refined through projects such as Tools for Scientific Thinking and Workshop Physics. These materials include videos, lecture demonstration sequences, activities for classroom use or homework assignments, instructor notes and software. In digital video analysis (see the section below), students use computers as laboratory instruments to make measurements on video images of real events. These techniques are being used increasingly in physics courses, and there is evidence that they are effective in teaching physics concepts. In spite of the wealth of mass-media and educational videos available that can be used in laboratories or student projects, very few existing videos are ideal for analysis in lectures or homework assignments. TheLivePhoto Physics project is meeting this need by producing a collection of digital videos that span many of the topics covered in a one-year physics course, including videos made with high-speed/slow-motion equipment that is not available at most teaching facilities. An innovative aspect of the project is that the topic selection is being guided by the results of physics education research. Written curricular materials using the videos in Interactive Lecture Demonstrations, distance-learning exercises and extended homework problem sets are being produced and classroom tested in a multi-year research-based development cycle. Field testing is taking place at two-year colleges and four-year colleges/universities with diverse student audiences. Computer software that extends the display and visualization capabilities of digital video analysis will be developed during the project. The project will sponsor workshops on the use of digital video analysis in physics teaching.

"LivePhoto" Analysis
Short videos, often just 20 to 30 frames in length, can be extremely useful in physics teaching. Not still photographs, but too short to be considered movies, these "live photos" can be played on the computer monitor at any speed, backward or forward. Moreover, just as a ruler can be used to make measurements on a photograph, positions in a video frame can be measured by pointing a mouse and clicking. The data that is generated can be graphed, analyzed in spreadsheets, compared to theoretical models, and even used to display vectors or points superimposed on the original video.
This use of the analysis of digital video as a learning tool in physics laboratory courses has become popular in recent years. In practice, a student does this with a computer program such as Tracker, Logger Pro or VideoPoint. For example, the student might analyze the acceleration of a ball undergoing projectile motion inside an accelerating elevator (see Figure 1).
elevatorexample.JPEG
After starting VideoPoint and opening the movie file, the video appears in a window on the computer monitor along with an empty data table. The student calibrates the system by clicking on the ends of an object in the video of known length (the person's forearm in the figure) that lies in the plane of motion, and entering the value of that known length. Then the student points to the ball in the first frame and clicks the mouse. The coordinates of the ball, measured in physical units thanks to the calibration, appear in the first row of the data table corresponding to time t=0. The video advances to frame number two, and the student clicks on the ball again, causing not only the coordinates of the ball but also the elapsed time for one frame of the video to appear in row two of the data table. Continuing in this way, the student generates data of the position of the ball as a function of time. Depending on the assignment, the student might graph the data in VideoPoint or export it to a spreadsheet for modeling. Other points, such as the outside window frame at the left edge of the figure, can be marked as well. By choosing another calibration length in the plane of the window, such as the window height, the student can use the window measurements for measuring the acceleration of the elevator itself.