Today the students took an assessment on drawing circular motion force diagrams. Here is what I gave them:
You’ll see why tomorrow.
We also had a pre-lab discussion to develop and experiment that will allow us to quantify radial acceleration. Through discussion, we arrived at looking at the relationship between radial acceleration and tangential velocity for a given radius. Most kids decided that the radial acceleration would be affected by the angular velocity, the radius and the tangential velocity. I asked if we could do an experiment where we varied the radius. A few realized that it was not possible because varying the radius will also change the tangential velocity *if the angular velocity is not changed)… so simply moving out on the circular to change the radius also changes the tangential velocity.
Here is the experimental set-up being used:
That’s a Vernier WDSS zip-tied to a meter stick on our record players. The tangential velocity will be measured using a Vernier Photo gate and One-Gate timing. The students will do the experiment twice… a small radius and a larger one. We did not get finished, so more data collection later. Here is a screen shot on my own data: