nist wtc7 kinematics physics students professors

New Kinematics Lab Kit based on the Motion of WTC 7

Kinematics Lab

In discussing my measurement of the freefall of Building 7 with one (reluctant) physics professor, the professor at one point protested, “I’ll take your word for it, for the sake of argument, but I have no way to confirm your claims for myself.”

That comment astounded me because I see the motion of the building as such a straightforward measurement. But upon reflection I recalled all the time and energy and collaboration that went into gathering all the necessary materials and information for the measurement: a suitable video, an appropriate software tool to make measurements on the video, calibration data, knowledge of video formats, etc. I realized that even with the requisite knowledge base and skill set, it would take a very motivated person to reproduce my measurements. I therefore collected together all the bits and pieces that went into my measurement and present them here as a kit that can be used by a physics teacher or handed to a motivated physics student as a lab assignment (or performed by a science-literate layman). The skills that will be learned in the process will serve a physics student well for other projects that might involve using video as a measuring tool.

Links to a zip file with the lab materials and links to the necessary software can be found at