Slow, Slower, Slowest


Measure speeds using the slope of a Position vs. Time graph.

Research Questions

How closely can you move your hand at designated speeds?

Setup and Materials

Motion Detector, interface unit, meter stick
Sample rate = 20 Hz, Duration = 5 s.


Practice moving your hand along a meter stick at speeds of 10, 5 and 2 cm/s and then use the Position vs. Time graph produced with a Motion Detector to monitor your motion. The slope of your graph line represents your average hand speed. Calculate the percent error between your target speed and the measured speed.

Data Table

Target Speed
Measured Speed
% Error
















(Respond to your research question, include results, and discuss error)

Suggestions for Further Research

Try measuring with hand speeds of 50 cm/s, 20 cm/s or even 1 cm/s

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Thank you to Roger Larson, the author of this lab. The webmaster has taken a few liberties with re-formatting Roger's original document and changing the photo.

Posted 1/21/10