RipStik in physical science: linear motion

To demonstrate linear motion while retaining some modicum of attention span from my social media saturated students, I rode a RipStik along the sidewalk in front of the laboratory. The activity is built around the linear relationship between time and distance for an object moving at a constant velocity. Thus my goal is to retain a constant velocity over the 36.9 meter distance.

Time (s) Distance (m) Pillar-to-pillar velocity (m/s) Acceleration (m/s²)
0.00 0.00

3.30 4.60 1.39
6.54 9.20 1.42 0.01
9.97 13.80 1.34 -0.02
13.14 18.40 1.45 0.03
16.10 23.00 1.55 0.03
19.32 27.60 1.43 -0.04
22.74 32.20 1.35 -0.02
25.86 36.80 1.47 0.04

The times were obtained by using a stopwatch to time the passing of pillars that are 4.6 meters apart.
Click on the chart to view a clearer image

The time versus distance data has a linear regression slope of 1.43 m/s. My velocity varied above and below that value by about seven percent. The acceleration data indicates only small variations in acceleration over the run.

The data was gathered in later one third of the period, the students are given as homework the task of plotting the data, determining the slope and thus the speed of the RipStik. The students are not asked to find the pillar-to-pillar velocities and accelerations, although that would be certainly be appropriate for a physics class. The class is a physical science class that is a survey of the physical sciences from mechanics to cosmology and all points inbetween.

The data is available in Google Docs spreadsheet.

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