Acceleration day two

Acceleration day one left open two possible equations that both fit the data, with the exponential reporting a higher coefficient of determination than the quadratic. Day two is intended to reproduce the left side of the curve. In keeping with last term, the sidewalk is marked in three meter segments. I wore my Hoka Mach 4 shoes as those provide a better board grip than the Hoka Challenger 7 series shoes. As long as the Mach 4 shoes are dry, all good. The complication in my first trial run was insufficient speed to reach nine meters. Oops. A second practice run with more pump put me over the nine meter mark with sufficient speed to make the u-turn at the top. 

Desmos

As with last term, omitting the vertex time helps smooth out the curve. The deceleration was on par with prior terms, perhaps slightly higher at -0.4 m/s² versus -0.3 m/s² fall 2023. I am not clear what the cause of the increased deceleration might be, but that suggests a reason I struggled to obtain the nine meter mark. The board is new last term, not sure why it would be slowing as much as it appears to be. 


Early arrival allowed me to preset the board with the Monday Desmos.


I also preset the board. 


Despite the presents, I was on the sidewalk five minutes later than fall 2023. The runs started at 12:15. On the first run I lost all momentum at the turn-around and came off the board. The second run did not make it to nine meters. I could not get the board up to sufficient speed. Old age perhaps. A third run failed when I missed the three meter timing mark. On the fourth run I slightly overran the three meter mark and nearly came off just past nine, but I eked out two measurements at nine meters and made it back down the course. 

Desmos

The delayed reaction to crossing three meters on the upbound side can be seen in the graph above. I knew the data had issues, but the push to hit nine meters was proving hit and miss this term. The board felt sluggish. Probably just me. 

I then showed that the exponential equation no longer explained the data, but the quadratic equation behaved in a manner consistent with the data. I then used the equation to cover the slope of the quadratic equation as the velocity of the RipStik. 

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