When we look up on a dark night, we see a sky filled with stars. The light from a star, like the light from a flashlight or a lightning bug, is one form of electromagnetic radiation.

Videos by astrophysicist/STOP creator that discuss the content, resources, & suggestions on activities.

Item: Activity 2 (Baseball speed)

Update: In the description of this activity, it is explained that the VLC media player can be used to advance frames of movies such that individual frames can be counted and compared with the corresponding elapsed time (which is displayed in the viewer). In some of our reviews of this process, we have discovered instances in which frames do not advance as expected when the letter "e" is used to step through the video. The result can be a miscounting of the frames, both when following the exercise to determine the frame time for the camera, and also when determining the time required for the pitched baseball to travel from pitcher to catcher.

At present, we have not identified a solution to this problem with VLC. However, we have tested the same exercise using the free QuickTime player available from Apple at http://www.apple.com/quicktime/ for both Mac and PC platforms. (The player is, unfortunately, not available for Linux platforms.)

The basic instructions for the activity are the same as described in the Facilitator's Guide, except that frames are advanced in QuickTime by using the arrow keys. One additional feature is that the frame time for the video file can be determined directly by using the "Movie Inspector" located under the "Window" tab. (For example, "FPS: 30" indicates a speed of 30 frames/sec.)

Overview (pdf)

Program Implementation (pdf)

Common Core State Standards (pdf)

Sample photos of posters displayed

Facilitator STOP Webinar