So I found this clip (see bottom) of a side conversation that I like and I wanted to see what other folks thought. It’s a bit too long (03:55) and there’s a lot going on, but I wanted to share it sort of well-embedded in its context.
This episode is clipped after the E1 groups have shared their energy theater versions of a ruler (bent back) smacking a metal ring. The acted out part consists of the metal ring sliding across the floor (post-smack). Before the episode included here, Lane has asked if there are differences in the representations that people feel like should get worked out. The issue of scale comes up.
A discussion ensues about whether kinetic energy refers (or should refer or can refer) to the coordinated motion of an object or the motion of molecules inside of an object. One issue in the room seems to be, can kinetic energy refer to both these scenarios at the same time? Another is, doesn’t thermal energy refer to this molecular motion? One teacher asks if this is all just semantics.
The episode here starts with a teacher in the front asking if it would be helpful in these situations to use the term kinetic or the term motion with younger students to avoid confusion later in life. At 00:58, Lane responds: motion to begin with, kinetic in the upper grades. A teacher in the back volunteers that the AAAS has avoided the term kinetic all together. Lane goes to the front and pulls up some standards to explore the language with everyone.
And here’s where I think things get very interesting: During the greater group discussion, Brian leans over to Sam and quietly asks @ 01:31, “So is heat- heat energy kinetic- is heat kinetic energy or not?”
Sam responds @ 01:36: “Kinetic energy is classically described as something that's moving as an entire body, an entire mass is going somewhere BUT in partic- particle theory heat is the vibration of particles so it is in a sense kinetic BUT the two classifications are separate.”
He pauses for a bit and then adds @ 02:36, ". . .Kinetic is not that hard to understand. Kinetic anything, kinetic just means motion, the kids can remember that, they're not stupid. One thing kids can do is remember vocabulary, if you use it enough, I mean, when we teach, we talk about kinetic learning to elementary school kids, we learn, kinetically by moving, and they know that and they tell their parents that kind of stuff and they get it. Don't treat 'em like they're dumb. They just don't know yet."
Finally, @ 3:28 Lane wraps up the discussion, "So I guess, I'm just going to go ahead and put the stake in the ground and say that if the ring is not moving then the motion energy has to go to zero." Notably, in the end, the word kinetic is absent from Lane's stake out.
Brian and Sam’s side conversation is something I’d like to maybe revisit again to figure out what’s really going on. Here, in this moment, is Brian asking Sam a question about what kinetic might mean juxtaposed with Sam kind of having a reflective moment out-loud that kinetic as a word is not that hard to figure out and everyone kind of knows what it means. Whoa!
Ultimately, what stands out to me is everyone is able to describe all these different kinds of energy events pretty well without the word kinetic. In fact, it almost seems like a lot more detail comes out in a description without the word kinetic. Isn’t that what physics is all about? Describing stuff that’s happening to stuff that’s happening in the world? I guess I see why we have to agree on common definitions of words, but do we? What kind of descriptions get lost when we give things a name?
Two things come to mind when I read your post, Virginia.
ReplyDeleteFirst of all, we had a similar discussion in Energy 2, on Tuesday afternoon. The discussion revolved around the question "What is mechanical energy?" Is it just energy related to motion? But that would be kinetic energy. Or is it the sum of potential and kinetic energy? But wait, which kind of potential energy? All of them? Or just gravitational potential energy? Amy and I also discussed that issue for a while in the chat. All of us seemed to be wondering whether or not "mechanical energy" was an established term in physics, or just something that was created for a freshmen level intro physics course. But why would we create such a term? I don't think we were able to resolve all these issues in a satisfying way. I might go back to try and find an episode from that afternoon and blog about it.
The other thing that came to mind is an ongoing discussion that I keep having with myself and that I had several times with Brian Frank and others: Do we really need to invent all those crazy names in order to describe things that we could describe in simpler ways? And, maybe even more important, do we really have to make students memorize those crazy names in order to enable them to communicate their ideas? Brian and I think not. On the contrary, we think that using terminology might inhibit clear communication of a student's idea. But then, there is the "regimenting discourse" idea that plays a HUGE role in the algebra project method. In the long run, we as scientists need to communicate ideas in a precise way, and using a common terminology makes this communication easier (provided everybody actually agrees on the meaning of a word and uses it accordingly...). So, if we want to educate our students to enable them to understand and participate in scientific discourse, we need to help them make the transition from their "intuitive language" to the discipline-specific "structured language."
I am sorry for vomiting out all those thoughts, I'm still in the process of structuring all this in my own head, but like I've pointed out before, I'm a think-while-talker.
Let me just end this comment in saying that I think it's awesome that we are having ongoing discussions about this important issue, especially because it is a KEY issue of the algebra project method.
I don't know if this is on point, Benedikt, I mean, on your point, or maybe it is on Sam's point about why have forms of energy. Hazel (who will be 4 in September) is starting to say spontaneous things about energy after having heard me say various simple things over the last couple of years. I think it is maybe starting to bother her when she is hot and tired (which is now an issue since we live in Texas) has both a surplus (hot) and a deficit (tired) of energy. How are we going to be able to speak clearly about whether we have too much energy or not enough, or possibly both, but in different senses? We'll see what she comes up with as the months go by.
ReplyDeleteWoot, we're talking about the difference between students' language and "our" language (as teachers), right now in E2 (2:10pm on Thursday, 8/11/11)! Not sure if that's related at all to the original post, but I wanted to post (and flag) that here in context to my earlier blah about unregimented/regimented discourse.
ReplyDelete