Karate chops and whitewater rescue

Blogs like these really remind me why I value this assignment. It gives me a real window into people's thinking, and with  your OEE background, I expect you have done a lot of writing about your OEE experiences.

Your reasons for wondering if you could survive in a physics or math classroom make a lot of sense. Interesting point about a group of 30 making discussion virtually impossible (we'll have to see how that plays out in our class of 27!).

Thank you for taking the time to list some of the Concept Test questions that kept you wondering, and I'm very pleased you took the time to go back through and see how you did. I hope that the test helps people to see several things--the potential limits of multiple-guess questions, and also how many different ways people can come up with to convince themselves that a particular answer is right.

It's very natural to be confused about the karate chop question. Force and energy are different--a force moving through a distance does work (and so the moving hand loses energy). But your line of thinking is exactly what Paul Hewitt must have been hoping for when he wrote that item, because he wants the question to help clarify that.

Thanks, Jamie!
Tom

Update on the concepts test from last week...

So I checked the answers to the 60 question physics test the other day after posting. I think I got about 18 wrong. I had starred about 10 as ones I wasn't sure about, or didn't agree with the answer we chose as a group. I think my instincts were right on about half of those. What really surprised me, though was some of the one's I got wrong that I didn't star. There were a few where I remember convincing the group of an answer I thought was obvious, but which turned out to be wrong. This has made me reflect on what I do and don't know about physics, but more importantly, how I approach something that I feel rather sure about. I think I can be fairly convincing when I am very sure I have the right answer, and this can sometimes get me into trouble. I'd like to work on slowing down a bit, and considering the viewpoints of others.

Whitewater Rescue and Physics Test

This weekend I taught a Whitewater Rescue course on the Gatineau River. I've spent a lot of time teaching on rivers, but this was my first time teaching this course. It was also an interesting opportunity to teach this course while at teacher's college. I'm trying to figure out if I could imagine myself teaching in a classroom. I think if I do, I'd like to bring some of what I enjoy about the outdoor education that I've taught. So I was thinking about what it is that I love so much about that sort of education.

Part of it is just having the chance to be outside all the time, which isn't very transferable to a physics class, though I definitely have some ideas of activities that could be run outdoors.

Another part is having a chance for activity and experience based learning. That applies very easily to paddling, and river rescue, which are by nature physical activities, but I think that one of the main obstacles is the size of classes, and ratios of students to teacher. I'd love to sit in a circle and have discussion based activities, or games to explain concepts, but that just isn't possible with a class of thirty students. I'd like to explore possibilities of having more engaging activities. I really like the setup of POE's, because they give a chance for some small group discussion/critical thinking, and really have a lot of attention grab.

Physics Test

On Monday we did a 60 question multiple choice test of physics concepts. In general, I'm not a huge fan of multiple choice questions, but I really enjoyed this test. Several of the questions generated a lot of discussion in our group. It was helpful to come up with a choice individually, and then discuss the answer, similar to the way a POE is run.
Here are some of the questions I found interesting/wasn't quite sure about the answer:
6. A karate chop delivers a force of 3000 N to a board that breaks. The force that the board exerts on the hand during this event is...

Conservation of force, and Newton's (second?) law...but some of the force goes into the board breaking, so I feel like it must be less than 3000 N. Couldn't come to a concensus

25. The "greenhouse gases" that contribute to global warming absorb
A More visible radiation
B More infrared radiation
C Visible and infrared equally
D Very little radiation

No idea for this one, though we had a lot of discussion about it. I'm not even sure if global warming is caused by absorption of radiation by GHG's or by reflection back to the surface of the Earth. I'm inclined to think the latter, and say D....curious to know more

35. The mutual induction of electric and magnetic fields can produce:
A light
B energy
C both
D neither

Not sure...

53. If the Sun collapsed to become a black hole, Planet Earth would

I really like this one! Debunks an often made assumption/exaggeration of black holes as all devouring objects. The sun isn't massive enough to form a black hole, but if it could, the change in gravitational pull on the earth would be inconsequential...I think that the distance is enough that they can be treated as point masses anyways.

56 and 57. Energy of particles released in fission and fusion....no idea. Gamma radiation is really high energy, but I can't remember much about this topic.

There's a bunch of others that interested me, but that should do for now. I'd love to get the chance to discuss a few in class.


Jamie