An introduction to forces

On Monday I simplified the RipStik demonstration by having a student hold the spring scale while I pulled myself. I did not try to measure the velocity nor acceleration directly. I used force = mass times acceleration to calculate the acceleration.


With a combined mass of 71.1 kg for the RipStik and I, the student saw a force of 40 Newtons. This yielded an acceleration of 0.56 m/s²


On Wednesday I covered Newton's laws from a momentum perspective. On the board above can be seen a calculation using Jereen, seen below, a visitor to the class on Monday.


I finished Wednesday with the yurt circle exercise - the day was sunny and clear. The exercise went well. The Thursday pulley lab went unphotographed. This term I eliminated the single load line pulley and opted to use only multiple line block and tackle set-ups. This eliminated spurious slopes of greater than one.

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