Today we WB’ed four of the six problems I had assigned last night. I choose one problem (a pogo stick problem because I have a pogo stick a class several years back all chipped in to get me) and I let them choose 3 of the remaining 5 to complete. I like these days because it gives us a chance to practice some conceptual questions. For example, one of the problems was a spring launching a mass vertically, I know you all know the problem. I asked about what effect doubling the spring constant would have on the maximum height… or the ‘take off’ velocity. I also asked them to predict the shape of a graph of height as a function of compression of the spring. If I had thought about it earlier, I would have had a Logger Pro graph waiting on the wings.. or better yet a Vpython (or Glowscript) or even Excel spreadsheet with slider bars. Well, there is always next year!
Today we went sledding. We used the LabQuest2 (well the x-accelerometer) to measure the acceleration as the students rode down the hill. There are a few things I had not thought about ahead of time. First of all was the fact that some kids did some spinning, also that it would be measuring the acceleration once the kids were on the horizontal part. Hopefully the were able to get some meaningful data. I did not really have a chance to look, I was serving up the Hot Chocolate!