Acceleration day one

Class started in A101 with a quick reminder of the linear graphs of last week. Students were then asked to predict the time versus distance graph for a RipStik run the starts from a speed of zero and then goes faster and faster.
The predictions were almost all linear.

The one correct forecast was highlighted post hoc. That correct prediction was mitigated by the inclusion on the same paper of two additional linear relationships. 

A thirty meters run was preset ahead of class with marks at 0, 1.5, 3, 6, 9,...27, 30 meters. The LRC start remains optimal as no swizzling need be done for the first 1.5 meters. Then a slow swizzle is begun. 

Perhaps the 27 meter should have been omitted, but the data worked out well enough. 

With measurements already marked off ahead if class, the run was completed in a single trial.

Acceleration was increasingly shaky out beyond 18 meters

The dismount was clunsy at best. I specifically asked the photographer to photograph me when I fell off. Excellent job of doing so.

I remain surprised at how well the LRC launch does, including seeing some acceleration out beyond 20 meters. 

The acceleration came in at 0.145 meters per second squared. 


There were still signs of acceleration out at 27 and 30 meters, with 30 meters displaying the highest speed attained up at 2.68 m/s. Fall 2025 I reached 2.98 m/s on an acceleration of 0.159 meters per second squared. I felt that though this term - I had taken no practice runs and my rear foot was not well centered to drive for maximum speed.  Practice runs and getting set up properly on the board are critical to achieving the highest velocities somewhat safely. 



The velocity regression came in at 0.140 meters per second squared. 



The velocity data is automatically calculated using table references in Desmos. I find this capability to be truly slick. 

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