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180 Photo Project- #teach180 Twitter Thread for 2018-2019
- Hour of Physics Code 2016
- Day 42: Hoverpucks
- Day 41: Last Day of the First Quarter
- Days 39-40: Lab Performance Assessment
- Day 38: Collaborative Review Notes
- Day 37: My Collection of Voting Slides for Preconceptions in Mechanics
- Day 36: Reteaching Electric Potential
- Day 35: Can You Hit The Roadrunner? Success!
- Day 34: Can You Hit The Roadrunner?
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Reflections on the dynamics of teaching
Action-Reaction 
Sorry, no mathematical questions come to mind.
Do you think its too difficult to see the increased rotation speed in the video? I showed this at the modeling workshop today and no one questioned that aspect. I’m wondering if this is a video that requires multiple viewings to observe some of the subtle aspects of the physics involved. To me the question is obvious, “Why does standing up (moving in) cause them to suddenly have trouble staying on the ride?”, but I think that’s because I’m looking for it.
Good point. Perhaps asking kids to describe what happened in the video FIRST, and THEN asking if they have any questions? Repeated viewings, of course, to make sure everyone agrees on the observations.
No, the inward movement is subtle, and there is a lot going on. They could be falling off because they are dizzy or drunk. If you want to emphasize inward movement, lose all the long warmup of people getting added to the carousel. That takes most of the time and doesn’t seem to lead anywhere you want to go.
I didn’t make this video, but it was the best I could find. I recall seeing one where there where 4 kids on a merry-go-round and then they walked to the center. The increase in speed was very noticable. However, in this video, I like the kids getting on and falling off. It adds more questions to investigate (e.g., should it slow down when people fall off, or is it just slowing due to friction?).
Frank, the video you are referring to came from Jearl Walker’s Kinetic Karnival..the rotation video. It was really great at showing rotatioanl inertia and conservation of angular momentum. I have a copy somewhere.
Awesome. Your comment reminded me that Dean Baird posted about Walker’s Kinetic Karnival. And sure enough, here it is: http://phyzblog.blogspot.com/2009/10/jearl-walkers-kinetic-karnival.html Looks like the rotation video is there.
The only problem is Walker put his videos on MySpace (!?!) which is blocked at my school. I’ll check them out at home later today.
There wa sanother one that had some odd music playing behind it that was even better..the kids would lean back…I’ll try to find that one