RipStik Accelerated Motion

In a previous article I shared the use of a RipStik in SC 130 Physical Science to demonstrate linear constant velocity motion. The ability to generate a relatively constant velocity by swizzling at a constant rate on level ground was useful to that demonstration. 

This term the non-linear motion of the rolling ball in laboratory two had already set up the concept of curved lines as changing speeds on a time versus distance xy scattergraph. This permitted me to move directly to data gathering for an accelerating RipStik.
This term I was rusty and did not generate the same top end as I have in the past. At the end of the run I simply "ran out" of acceleration capacity.

Pillar Time (s) Distance (m) Velocity (m/s) acc (m/s²)
one 0 0 0
two 4.05 4.6 1.14 0.28
three 6.91 9.2 1.61 0.17
four 9.19 13.8 2.02 0.18
five 10.66 18.4 3.13 0.76
six 12.44 23 2.58 -0.31
seven 13.85 27.6 3.26 0.48
eight 15.23 32.2 3.33 0.05
nine 16.66 36.8 3.22 -0.08

Although my acceleration changed during the run, overall the acceleration held close to 0.20 m/s² The run was no where near as good as the one last fall, but then this is 2011 when anything that can go wrong will go wrong at the worst possible time and worst possible way.
A closer look at the velocity versus time suggests that the acceleration was roughly constant up to the third pillar, and then further acceleration was inconsistent.
Given that the fifth column realigns with the constant acceleration, the data suggests steady acceleration should be possible over the first four to five columns but not beyond. Slower acceleration rates might also be an option, but might be harder to maintain. Some form of beats that increase steadily might help the rider increase speed in a steadier fashion.

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