Linear velocity

Monday began in A101 with an opening question on how time is related to distance for motion at a constant rate. 


Wednesday was used to introduce use the split timing capabilities on the stopwatches, with the students walking 30 meters and determining their walking speed using Desmos. Splits were every three meters.

The Monday RipStik run was at 1.75 m/s. 

Thursday the lab opened with a framing question and the table layout

Data was then gathered in the field. An east wind had me reverse the direction. At 8:00 the slow balls were perhaps a tad too fast. As was done fall 2023, the slow and medium speed balls were both timed on three meter splits. The fast ball was timed on a six meter split. This appeared to work moderately well, as it had last fall. This removes the need to remeasure for each run speed.

Friday I plan to cover slope zero and slope undefined. Might cover pace versus velocity. Magnus effect might be worth demonstrating. 

In the 11:00 section I was little more prescriptive in the table layouts by including the distances.


I knew I would be working westbound due to the wind, but I backed up six meters in the 11:00 class. This proved problematic. There is a hidden slope to the sidewalk in front of the building that leads to balls arcing off to the right. To get a ball down the length of the sidewalk required aiming left of center. 

Joyleen and Lilly Rose enter data into Desmos

On Friday I backed up to cover a 95% confidence interval on a Jergens soap data set from week one that had a density of 1.01 grams per cubic centimeter. I tried to explain that the uncertainty in the data leads to uncertainty in the slope, and this means the slope can vary from 0.96 grams per cubic centimeter to 1.06 grams per cubic centimeter. Hence the data cannot predict what the soap will do, and floating is a possibility.

I then covered a slope of zero, and a vertical line. I did the usual deep dive I do into the issue of zero in the denominator. The math says it is impossible, and it is impossible. I mean, setting aside quantum entanglement... I then demonstrated the Magnus effect to close the period using the curved paddle and a ping pong ball that remain stored in the prep room for this purpose. 

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