Respiration is Degrading

View my Prezi here

This clip is from a whole-group conversation. It is preceded by Steve asking "Is there any other kind of degraded energy besides heat?" The clip begins with Madonna mid-sentence; her complete sentence is, "Madonna: In respiration, the energy contained in the CO2 bonds and your water at the end are not necessarily useful."

Madonna is positing the chemical energy of CO2 and water (the products of respiration) as "degraded energy".

I found support for Madonna's idea in Campbell:

The products store less free energy per mole than the reactants; that fits our colloquial definition of "degraded"=not useful.

It also fits with Rachel's idea of degraded=less of a gradient, I think--because the products store less free energy, there is less of a gradient between them and the products of any future metabolic reaction that might involve them. Glucose is non-degraded--and useful--because there is a big difference in free energy between it and the products of respiration, a metabolic reaction that the cell can carry out. The cell CANNOT carry out a reaction with a similar release of free energy from CO2. But if it could...then the chemical energy in CO2 would be useful.

I got this idea from Campbell, that debunks the biologist's shorthand that "energy is stored in bonds". "It is important to realize that the breaking of bonds does not release energy," as biology teachers, yours truly included, often tell their students. The "stored energy" we refer to, says Campbell, is actually "potential energy that can be released when new bonds are formed after the original bonds break, as long as the products are of lower free energy than the reactants."

 There are a few things I find curious about this explanation:

If the energy "can be released", then why is it not appropriate to call it stored?

With the phrase "potential energy that can be released when new bonds are formed", is Campbell reiterating the potential energy=possible energy misconception?

Can I help myself here by renaming potential energy as gradient energy or difference energy? In that case, the potential energy is not in the reactants, but between the reactants and products. This jives with something I already know about gravitational potential energy, which is that the amount you have is relative to where the "bottom" is.


[00:00:00.00](Steve: Is there any other kind of degraded energy besides heat?
Madonna: In respiration, the energy contained in the CO2 bonds...)
 and your water at the end are not necessarily useful
[00:00:05.10]they're degraded to you, they weren't utilized
[00:00:08.04]you're using your ATP to do work for your body
[00:00:12.23]but the CO2 and the water that is given off
Debra: They're lost.
[00:00:18.00]I don't know--is that degraded energy?
[00:00:21.20]There's still energy in the chemical bonds...
[00:00:28.18]And the same thing with a battery.
[00:00:30.04]In a battery you have movement of those electrons due to a difference in electrical potential or reduction potential
[00:00:41.06]but it's degraded once...
Debra: Well it's the concentration difference that drives it

[00:00:49.01]Madonna: In a copper battery, once that copper has received its electrons and becomes a solid, it's no longer...

[00:00:57.29]Steve: So those are degraded matter. I'm trying to think...
[00:01:00.21]if you've got the carbon dioxide when you're done
[00:01:04.25]it's had the transfer of energy by breaking its bonds
[00:01:12.11]no, reforming more stable, tighter bonds
[00:01:15.10]so they've given up that energy
[00:01:18.07]so now you've got a matter leftover

[00:01:21.14]Madonna: that contains energy

[00:01:24.01]Steve: But does it?
Madonna: Yeah! The carbon to oxygen bonds have energy

[00:01:30.07]Steve: But it bonds at a lower energy than it started
[00:01:33.21](Don makes a "downhill" gesture) It's been degraded.
[00:01:36.12]It's a much lower potential

[00:01:41.01]Brad: The energy density in sugar is higher
than the energy concentration in CO2 and water

[00:01:48.15]Debra: So then it IS coming down a gradient

[00:01:54.10]Madonna: it would be waste energy that you're putting off

I-RISE congress 2013 - Jesper Haglund

Below, I share some of the slides I presented at the I-RISE congress and some reflections along the way.

I am a postdoctor in Science Education at Linköping University, Sweden. Dring my stay in Seattle, I was asked about geography and climate, so I started off with some comparisons:

These overlays comparing the latitudes of Europe and North America show how far to the north Sweden (and also Poland) are located. We thank the Gulf Stream for making our countries habitable.

 

I have experience of recording and analysing video data from my previous research, but never in the organized form that has been developed within I-RISE. While I-RISE records what happens throughout entire courses, I have previously been involved in short interventions only.

There are many commonalities between the lines of research being done within the Energy Project at SPU and in our group at Linköping University. From a science content perspective, we have a shared interest in thermpdynamics, and in particular in concepts relating to its second law, i.e. efficiency and energy degradation. We have also both analysed language in science and science education from the perspective of conceptual metaphor. What I learned most about being an I-RISE scholar, however, was to get to know about the structured approach to qualitative research, involving taking and sharing field notes and making blog posts, so that episodes that had caught one person's attention quickly could be discussed within the group.

 

 

In all, I found my time as an I-RISE scholar a very rewarding experience. Apart from getting to know about the professional development at SPU and the research on its outcome, it provided good opportunities to build networks within the PER community.

 

In addition, I think that the way conceptual metaphor was introduced in E2 and how the participants came to approach the matter holds an interesting story that may be the embryo of a manuscript. In previous research, it has been shown that conceptual metaphor is prevalent in language in scientific discourse and science textbook. However, we have struggled to establish eduactional implications of such analysis. Reactions reviewers and at conferences have sometimes been of the type:

 

“OK, you have found that science language is full of metaphorical language. So what? How can I as a science education researcher or teacher use that?”

 

I think that we have gathered data in E2 which can help us respond to such reactions in two ways:

• Science teachers find the idea of looking for metaphorical aspects in students’ language intriguing and worthwhile. It may help them analyse the students' thoughts and respond to them.
• After a brief introduction to conceptual metaphor, some science teachers independently reach the conclusion that we cannot talk about energy without recourse to metaphor (as has been argued in general about language overall by Lakoff & Johnson).

To the best of my knowledge, these arguments have not been put forward before, and may provide a basis for research collaborations in analysing the participants' dialogue and a useful manuscript pitch.



Using ET as a reconciliation tool... (Afternoon ET 08-09 saga - part 3)

This is the third (and probably last) video from the Lowering ball saga.

Right before this episode, Barbara was explaining her reasoning on how is the energy story while lowering the bowling ball at a constant speed. Her story focuses on the ball having lots of potential gravitational energy at the beginning, and as it is lowered it loses potential energy, which is transformed into kinetic (since it is moving). Since they are working to define the ET they will represent for this scenario, some of the group members let her know that they can not lose energy (since it is conserved), nor can add extra kinetic energy (since it is constant speed). Since the discussion was not leading to a change, they decide to explore Barbara's idea while acting her ET.

**Warning: this video contains some noise in the audio. 

It is 3+ minutes, but I think it has a lot of things to discuss about - meaning: it is worth it!**

[00:00:01.08] Trevor: So if I am potential and somebody is kinetic and we are moving in the air, so this is the beginning right? 

[00:00:08.10] Barbara: Are you the ball or...

[00:00:09.03] Trevor: This (the rope) is the ball, and we are going to ignore everything else just focus on this. As the ball moves down more I have to do something (noise)

[00:00:21.20] Barbara: You changed to kinetic.

[00:00:22.69] Trevor: OK, now don't we have more kinetic energy than we started with?

[00:00:27.28] Krista: So we will be going faster like () it will be dropping faster?

[00:00:30.27] Trevor: We have to be going faster

[00:00:31.26] Barbara: Well you need, the guy is... No because the guy is putting resistance.

[00:00:38.16] Krista: So then we have to include the man our-

[00:00:40.24] Barbara: You use less pot- No, you use less potential and that became kinetic and, and it still can fall so-

[00:00:44.74] Trevor: But where do I (potential) go?

[00:00:49.00] Barbara: To kinetic, and you ended up staying there (the ball).

[00:00:51.26] Krista: But now we have () kinetic energy, because now we are both kinetic.

[00:00:55.11] Barbara: No, they were both potential and they both went to kinetic, that's (Trevor: No) what I am saying.

[00:00:59.20] Krista: So, I think we need more people.

[00:01:01.21] Barbara: Ok, so you have one kinetic, two potential and you all three are potential. No! You need more of your because the three of you- you need five, four.

[00:01:09.22] Krista: Hypothetically, go ahead. Walk us here.

[00:01:12.21] Barbara: Four potential, before it starts lowering. But one- When it's moving say one kinetic, three potential

Trevor: Ok

Krista: Ok, so what happens when 

[00:01:23.04] Barbara: And then one other changes to kinetic. And it still moves past the waist.

[00:01:30.03] Trevor: Are we still moving faster 'cause we have two kinetics, and we started with one?

[00:01:35.05] Barbara: Maybe one can go to thermal.

[00:01:36.19] Trevor: So you think thermal's in the ball?

[00:01:40.28] Barbara: Thermal in the- I don't know where, not in the ball. () in the air...

[00:01:43.02] Krista: Where do I (kinetic) go?

[00:01:44.06] Barbara: Maybe call it in the air. Some kinetic in here (the ball), thermal and kinetic in here. Very simplified.

[00:01:56.22] Barbara: (Maggie is transferred and transform into thermal in the arm) No! We need potential in here (the ball).

**Different voices at the same time**

[00:02:06.29] Emma: So far in the examples we've seen, this is the problem I am having. When we have some kinetic energy and some thermal energy exiting to the air from an object that's usually a really small portion of the energy. And so I am really hesitant to say that of all the potential energy in the ball- 

[00:02:25.17] Barbara: But it still moving when it is here, so you can have kinetic energy in the ball.

[00:02:29.10] Emma: But you can't have more than you started with because the ball speed is constant. So you can't gain kinetic energy, which means you have to be given energy.

[00:02:34.10] Barbara: Well, so what _you_ guys want to do. 

[00:02:39.15] Trevor: I think we need to put these people who are changing from potential to something else have to go into the arm. Because if you ima-

[00:02:46.00] Barbara: Not from the ball.

[00:02:48.22] Trevor: From the ball (Other voices: from the ball).

[00:02:51.24] Krista: Maybe is not a direct path like that kinetic- No, potential. Go ahead.

[00:02:56.07] Barbara: Would you say it again, what you-?

[00:02:57.09] Trevor: So I am saying potential, from the ball, has to go into the arm and I think it's thermal, because the arm doesn't get going faster either.

Emma: Yeah.

[00:03:07.16] Barbara: So the potential from the ball goes into the arm.

[00:03:09.27] Krista: I mean through a chemical process is heating up the arm, not directly-

[00:03:14.28] Trevor: I think it's kind of directly

[00:03:16.26] Krista: I mean, but it is a direct reaction to what is happening (Barbara: the ATP). So it's causing the arm to heat up.

[00:03:24.11] Barbara: And whenever ATP (is hydrolyzed?), it changes the shape of the molecule. That's how the body gets work done. 

[00:03:33.14] Barbara: But you know what, I want to see what- You guys play yours now.

I presented this video in the I-RISE Congress, and basically I could use this video for 10 different purposes. But what I (personally) am more interested of, is how they decide to use the ET as a tool of conciliation with Barbara. Instead of remain in a discussion trying to persuade her (we consider Barbara and the group initially were talking of different things), they decided to understand where is she coming from, and then question her in the blank spot that she has not addressed. I consider this group dynamic shows responsiveness and I can almost see how with the ET performance I can observe the accommodation and assimilation process of Barbara (magic to my eyes). And I simply love how Barbara, after all the questioning they made to her model, the modifications she decide to include, and the addition of new elements, at the end she stills recognize that ET as her own.

Some other issues that we discussed with this episode is how they see thermal energy as the answer to conserve the energy in the system, but they have problems trying to explain where should it go, or why it happens.
ATP shows up again, if it weren't because of KD explanation, I wouldn't be aware of it (long time since I had bio classes). Now I realized that it is a thing while trying to explain the scenarios during E1 and E2, but I could not say if this is a sign that the instruction of the PD should address or if they prefer to simply mention it with no further details (those two positions has been brought up in more than one occasion).
We also noticed the implication of representing kinetic energy as the people jogging. Rachel said she doesn't like it because it allows to mix the substance and level energy ontology. In my personal opinion, I liked it because I was able to see she sometimes tried to mixed both ontology, but she also notices it and go back to her regular pace.

This is the end of the Saga. I share the other links if you are interested in more details, or simply get more information of what happened before.
Conceptual understanding vs Equations (Afternoon ET 08-09 saga - part 1)
Forces vs Energy... (Afternoon ET 08-09 saga - part 2)
I-RISE Congress - Lowering at a constant speed

I-RISE Congress - Lowering at a constant speed

Thank you again for such a great experience! I am sharing the slides of the congress presentation.

I am the first I-RISE Scholar coming from México. I show you where I am exactly from.

During High School, in a aptitudinal test they told me I had good aptitudes to go for a exact science carreer or for humanities. In my mind that didn't make sense, how can you mix them both? I decided to study a B.Sc. in Physics Engineering. A couple years after, I discovered there was a PER group in my University and decided to join them. It was in that moment that I realized that there was a way to mix both of my strengths, since then I decided PER is was I would do.

Basically, I started doing my fists steps in PER as an undergrad. Then I decided to go for a Ph.D. in PER, continuing working with Genaro Zavala, now as my adviser. Two summers ago Rachel went to my university for a summer workshop about video analysis. In that moment I decided that was what I wanted to do. I arrived to Seattle on April for a six month research visit to develop my qualitative research skills (my PER group do not use video analysis that much).

Due to time limitations, I could not analyze both days as I planned originally. I wanted to see what were the differences that made one day more productive than the other. Instead I decided to study in detail the second day (more productive than the first). As a clarification, E1 has already worked in ET in previous days, but not during afternoon. So it was the first time I observed them doing ET alive, but not their first time doing ET.

I share the video here, but for more detail please check the post: Forces vs Energy... (Afternoon ET 08-09 saga - part 2)

**Warning: There is wind noise in the audio**

I share the video here, but for more detail please check the post: Using ET as a reconciliation tool... (Afternoon ET 08-09 saga - part 3)

**Warning: there is also some noise in this one**

As conclusion, thank you for helping me developing my qualitative research skills. I really appreciate having a space where people get engage in this kind of discussions and gives you productive feedback to improve your opportunity areas.I am really wishing I have the opportunity to keep working with this two ET, because I felt I needed more time to finish the analysis.

Forces vs Energy... (Afternoon ET 08-09 saga - part 2)

This is the second video from my E1 Afternoon ET 08-09 saga. The group is making agreements on how to make the ET for a bowling ball being lowered at a constant speed. This video is tightly related to the first part of the saga Conceptual understanding vs Equations (Afternoon ET 08-09 saga - part 1).

During E1 they have been talking about forces for more than one day. In this video we observe Cindy making an analogy to try to understand how to represent the opposition exerted by the hand while lowering the ball at a constant speed.

[00:00:00.00] Cindy: If I am pushing against her, all right?
So, I am pushing against her and, but you- you're, you are resisting to the point- You are resisting to the point that I can't move you.
[00:00:10.24] Cindy: Amm, is this kinetic energy?
{different voices from the group saying no}
Trevor: There's no movement
Rob: Weren't you saying (to Barbara), weren't you talking about-
Cindy: () is not moving.
Barbara: So, can I ask a question?
[00:00:17.28] Cindy: So, I am lowering a bowling ball gradually (gestures of the ball being hold by something)
Maggie: -at a constant
Cindy: -at a constant... Do I have an opposite kinetic energy -I am, I am just trying to throw this out there.
[00:00:31.14] Cindy: I don't know what's correct and what is incorrect but, could part of that chemical energy be converted into kinetic energy as well in -in the arm system?
[00:00:44.04] Rob: I was trying - I was having a hard time of exp- verbalizing that, you know? Exactly what you are saying with you resisting so the energy -kinetic energy is going downward and you are pushing back with a _force_ in the opposite direction. But the force is not the same as energy
[00:00:59.19] {different voices of the group agreeing}
Rob: And I... So the energy lose, I am not- So, you know? There is no kinetic (noise) slowing down the kinetic energy. (noise) in the opposite direction.

 Rob mentions he had problems trying to verbalize that, he might refer to the discussion presented on the first part of the saga. In this episode we observe how they realize forces and energy are different, they consider that when a force is applied in the scenario they should represent it somehow in terms of energy. They constantly talk that they are different, but still can't explain the energy story involved in the scenario given with certainty.
[Next episode of the saga: Using ET as a reconciliation tool... (Afternoon ET 08-09 saga - part 3)]

Stirling engine ET representing energy density

In E2, 130815, Thursday AM, the teachers were asked to enact a Stirling engine in an energy theater. They had been shown the engine the previous morning and started sketching energy diagrams, but had not carried out an ET.

The engine consists of gas contained in a cylinder,separated into two compartments by a styrofoam wall. If you heat the gas in one of the compartments with a hot cup of coffee, it will expand, which moves the separating wall. The wall, in turn, is conncted to a balanced wheel with a rod, so that the wheel starts to rotate when the wall moves. Finally, the wheel is connected to a piston, which compresses the gas in the compartment that was not heated, so that the styrofoam wall returns to its starting position. This closes the cycle of the engine.

I attach the entire ET (25 minutes, three clips), since I think it gives much insight into how the groups gradually developed the idea of representing "energy density" in the form of participants' distance from each other within a particular object. The closer they are to each other, the higher the energy density. This can be compared to another representation, posted by Abby in 2011 (http://scherrenergyproject.blogspot.com/2011/08/shrinking-people-to-represent.html) of people "shrinking" vs. speading their arms, indicating the same amount of energy, but more or less useful to do work.

They enact the entire process in three steps: First, the cylinder starts go get heated, so that the engine starts to move. Then, there is the steady-state operation, where thermal energy goes to surrounding air, driven by a gradient in temperature and different thermal density at the heat source vs. heat sink. Finally, when the coffee has reached room temperature, the engine will stop and thermal energy will be evenly distributed.

 

The notion of "energy density" is found useful by the entire class, including the instructors, and this ET pair of groups is later asked to enact their ET in full class. Energy density contributes to understanding the difference in usefulness of a certain amount of energy in different circumstances.

Another thing to note: Gail is checked out most of the time.

Group 3's energy diagram:

A synthesised energy diagram, when the engine is driven by a temperature gradient between the atmosphere and a pack of ice, based on those of all groups:

Energy is money analogy

In E2, 130815, Thursday AM, they made extensive use of analogies between energy and money, when dealing with loss/waste vs. usefulness. It is different if there are 4 people with $100 each vs. 1 million people with one dollar each, with examples when the rich and poor get to interact.

Leslie came up with this idea: "It's not how lucky I am, it's where I live." In other words, what you can do with a certain amount and form of energy depends on the energy inthe surroundings.

Sture Nordholm has thought more of how to map thermodynamics to money in education:
http://pubs.acs.org/doi/pdf/10.1021/ed074p273.

I like this analogy by Paul Atkins http://www.google.com/books?hl=sv&lr=&id=kJyXzvkXWBAC&oi=fnd&pg=PT2&dq=atkins+galileo%27s+finger&ots=Z_5l1WXMZZ&sig=Ukrtm9TUcfrbpde8uY7YbgGEeKo:
"The analogy I like to use to show the connection [between the interpretations of entropy in macroscopic thermodynamics and statistical mechanics] is that of sneezing in a busy street or in a quiet library. A sneeze is like a disorderly input of energy, very much like energy transferred as heat. It should be easy to accept that the bigger the sneeze, the greater the disorder introduced in the street or in the library. That is the fundamental reason why the ‘energy supplied as heat’ appears in the numerator of Clausius’s expression, for the greater the energy supplied as heat, the greater the increase in disorder and therefore the greater the increase in entropy. The presence of the temperature in the denominator fits with this analogy too, with its implication that for a given supply of heat, the entropy increases more if the temperature is low than if it is high. A cool object, in which there is little thermal motion, corresponds to a quiet library. A sudden sneeze will introduce a lot of disturbance, corresponding to a big rise in entropy. A hot object, in which there is a lot of thermal motion already present, corresponds to a busy street. Now a sneeze of the same size as in the library has relatively little effect, and the increase in entropy is small."

Trevor as a Case of Negotiating Science Identity

The E1 I-RISE crew has poked fun at Kara and me for our mild obsession with Trevor.  What fascinates me about Trevor is that, throughout E1, he stably positioned himself as a physics expert.  He rarely expressed interest in the thoughts of his peers or asks for help; he regularly asserted himself as an authority, explaining things to his peers or to the class; and he regularly spent breaks (or class time) talking one-on-one with Lane or Adam.  It would be fascinating to connect Trevor episodes to the literature on identity as a rich, extended case study.

I spent yesterday and today pulling a few episodes to illustrate some of Trevor's antics.  I'm not going to put these in order; instead, I'm going to organize them thematically.

These first three episodes illustrate Trevor explaining something to his peers or to the class.  I think this deserves a much more careful analysis, but, briefly, I see Trevor positioning himself as an expert by:

• Using technical (sometimes quantitative) language (e.g., compression, tension) and referring to well-known figures in the scientific community (e.g., Richard Feynman)
• Asserting his role as teacher-expert by moving to the center of the room when his talking, proposing a 'fun' experiment his peers can do at home, offering his solution without bidding to Cynthia, asking leading questions to his tablemates, etc.

I'd love to know if you see other bids that Trevor makes to be recognized as an expert in the videos below.

Trevor explaining to the class

Lane: What do folks think is happening at the micro level with the meter stick?
Trevor: I know from engineering with bending, you have compression on the, the bent side, and you have the tension on the other side, so, so, you know, if you think about the molecules...
(Lane hands Trevor the meter stick, and Trevor rolls into middle of room.)
Trevor: ...on the bent side here, they have to be closer together (pause).  Because you're reducing the distance between them.  And the ones on this side have to be farther apart.  So you're sort of stretching both.  You're compressing this, and you're expanding this and both kind of want to go back, but I don't know why they want to go back. [Shrugs shoulders]
Cynthia (?): I think it's that they have been pushed opposite and so they have the potential to actually move.
Sara (?): [...] shared electrons, so they're, I mean, the meter stick is all made of wood so it's mostly carbon, so they've shared so many electrons with things around them that if you pull them apart from each other on the far side of the meter stick, they should want to go back to where their electrons are.
Trevor: Cause they're like magnetic, radio (wiggles fingers), you know, yeah.
In the background: Yeah.
Rob: The inter-molecular attractions.
Trevor: Attractions.
Rob: Too much electron sharing then you'll have combustion.  So we're not going to go there, but the inter-molecular attraction between the complex carbon molecules, organic molecules.
Trevor: So then why with clay, I don't know.
Sara (?): Because clay is not made up of carbon, so it's bonded differently.  So it's got less bonds [...]?
Margaret: Yeah, it's just [PZs?].
Rob: Less forces.
Trevor: Forces.
Sara (?): So it's got less inter-molecular attraction.  So.
Trevor: I don't know.
[Teachers talking in the background.]
Rob: Or it could have more.
Sara (?): It's got different.
Trevor: You know, we made bridges out of spaghetti, and spaghetti's [...] tension when it's not cooked, but under compression, it (snaps) like that.  And so when you try and bend it, you try and bend a piece of uncooked spaghetti, it snaps. (Lane takes meter stick back.) But if you pull equally on the ends, you, it'll hold up lots and lots of weight.
(Sara says something I can't hear.
Trevor rolls back to place.)
Trevor: [...] Property, it holds up under tension but not compression, so if you try and bend it, by compression, it snaps, right?
Lane: And that suggests to me is the difference, the molecular difference between something that wants to spring back and something that doesn't want to spring back, it must be pretty complex.  Because if cooking spaghetti changes it from, you know, from wanting to spring back to not wanting to spring back, then that tells me that I would at least have to understand what cooking spaghetti, what the molecular, you know, of cooking spaghetti is.
(Someone says something in background that I can't hear.)
Lane: Well, that's one way to do it, right.
Trevor: And I'll just throw out for, a fun experiment for you guys to make a mess in your kitchens.  When you break a piece of spaghetti, it almost always breaks into three pieces, never two.  Richard Feynman used to sit around and just break spaghetti with his frinds and like talk about why that is.  And it's very complicated to understand why that happened, but standard spaghetti, you know, just start snapping, always breaks into three.

Trevor explaining to Cynthia

Trevor: See, this is what I was trying to do.
Barbara: Call it 1, 2, 3, or A, B, C.
Trevor: That's what I was trying to do last [...].  Last time I was trying to put numbers on it.  Allright. (Barbara and Maggie are talking in the background.)
Cynthia: Because assigning numerical value becomes more confusing.
Trevor: It just helps me.
Cynthia: I, I agree.
Trevor: Well, like, so, like, if there is 1 J of kinetic energy and 10 J of magnetic energy on this ball, okay?
Cynthia: Right.
Trevor: Well, this one is going to have less magnetic energy cause it's almost to zero.  I'm gonna call this one zero.
Cynthia: Right.
Trevor: But it's gonna have almost the same amount because it really loses the most when it gets in here, right?
Cynthia: Mmhm.
Trevor: This is where the magnet really affects it.  So I said 9 J.  So this is the situation at the beginning.
Cynthia: Mmhm.
Trevor: So using that as a model, both, since this is touching these at zero, both of these are touching, these are both zero, right?
Cynthia: And then.
Trevor: And then this is out here at the 10 J mark.  Well then how many J do I have left?  I have 19, 20 total J here.
Cynthia: Right.
Trevor: And I only have 10 here.  So that must mean that this must have 10 J worth of kinetic energy.  Which is 10 times more kinetic energy than I had before.  So that's why it goes faster.
Cynthia: Right.
Trevor: In my head.
Cynthia: Yeah.  I mean, that does make sense.
Trevor: I think it makes sense to throw numbers in there sometimes.
Cynthia: Well, unless you throw numbers it's kind of this magical thing that's happening that you can't evaluate.
Trevor: And it's so hard to track which is increasing and by how much and all that stuff without numbers.
Cynthia: Right, and I think the key here is that zero value, and then you have to account for what was here to begin with and...
Trevor: Zero makes it a lot easier.
Cynthia: Yeah.
Trevor: But, I mean, if I added to all my magnetic energies.
Cynthia: Mmhm.
Trevor: If I added fifteen to all of them, it's not gonna change anything.
Cynthia: Right, it's not gonna change as long as it, you've added...
Trevor: ...to all of them.
Cynthia: ...it to all of them, right.

Trevor asking leading questions to his group

Barbara: Okay, we can talk about [h].
Maggie: Okay.
Barbara: I said it speeds up.
Trevor: Wait, hold on, did you say g, too?  Can we go back to g?
Maggie: Sure.  Okay, (reading) so based on your answers to e and f, would you say that the magnets and balls have more magnetic energy when they are tightly bonded or weakly bonded?
Barbara: I said it depends on they're talk-, this is the question I asked Adam. 
Maggie: Mmhm.
Barbara: If it's talking about this close from the magnet.
Trevor: That's, so, well distance from the magnet is, it determines both magnetic energy and how tightly bonded they are.  Would you agree with that.
Several: Mmhm.
Trevor: So (plays with experimental set-up).
Maggie: What if the mag-.
Trevor: Which ball is more tightly bonded?
Barbara: These two.
Maggie: [...]
Cynthia: The two that.
Trevor: Out of the two I'm pointing to.
Barbara: This one.
Trevor: This one.
Maggie: Yeah.
Trevor: Which one has more magnetic energy?
Barbara: That one.
Cynthia: This one.
Trevor: Okay, so the less tightly bonded one...
Cynthia: The more.
Trevor: The more, the more, the less tightly bonded is, the more magnetic energy it has.
Barbara: Thank you.
Trevor: Now that's sort of counter-intuitive, which is why they're asking the question.
Maggie: Okay, that was the problem.
Barbara: Yeah, that's not what I said.
Trevor: But you knew it. 
Barbara: Yeah.
Trevor: When I asked it that way, you had the answer!
Barbara: Yeah, but it's asking it that way.  That's what your teachers are doing, maybe in Baltimore.
Maggie: So even though it sounds counter, even though it sounds counter-intuitive, it makes sense.  Cause that was the problem I had, is I said, well, the further they are, the weaker they're bonded, and then the further they are, the more magnetic potential energy they have.
Trevor: I like [the way that sounds?].
Maggie: I teach logic, what do you want?
Trevor: QED!
Maggie: Therefore, but it didn't make sense, the more magnetic potential energy,...
Trevor: The weaker the bonds.
Maggie: The weaker the bonds, and that.
Trevor: Cause they have more POtential to release that magnetic energy.
Barbara: I wish they would stick in potential because it makes more sense when potential is in there.
Maggie: It still doesn't make sense, but that's okay.
Trevor: That still doesn't make sense?
Maggie: I don't like it any [...].  Logically, it foll-.  The logic is sound.  [What actually happens I'm not sure].  Like this last statement sounds wrong.
Trevor: What it, the more, the more, because the closer you are to something.
Maggie: Wait, hang on, hang on.  Let's change it to.
Cynthia: (Talking to herself, repeating Trevor's words:) The closer.
Maggie: I change the 'm' to 'g'.  That makes sense, the more gravitational potential energy...
Trevor: The weaker the gravity.
Maggie: Yeah, that actually makes sense.
Trevor: Between the two objects, right?  It's further away.
Maggie: That means it's higher. Okay.
Trevor: It has more potential to fall.
Maggie: It's just that magnets are a little unfamiliar to me.

Even Trevor's facial expressions when talking to his peers suggest to me that he is positioning himself as the authority:

(Play without sound)

This final episode (below) is so rich.  It shows Trevor's group members taking up his bid to be recognized as an authority and recognizing him as an expert.  This episode happens between the "Trevor explains to Cynthia" and "Trevor asks his group leading questions" clips above:

Barbara: I think I got it.  Now I'm gonna try to write it.
Maggie: Wait, say it one more time.
Barbara: Okay.
Maggie: Cause I think I was where you were yesterday.
Cynthia: Can I...
Maggie: ...Like I sort of have it but barely.
Barbara: Okay.
Cynthia: This is so complex, would it be possible to.  Barbara, would you mind if I kind of videoed and recorded this, just?
Trevor: What we're saying, you mean?
Barbara:  Not me talking.
Cynthia: Not you talking.  Okay, then I won't.
Barbara: Cause I'm not gonna say it right.
Trevor: You can videotape me talking.
Cynthia: Oh, thank you, Trevor!
Barbara: You get Trevor talking, get Trevor talking cause he'll say it right...
[Trevor says something to Maggie.]
Cynthia: This way I can prove I'm actually in a science class.
Barbara: Okay, so...
Maggie: ...So.
Barbara: Get it at 90.  So we'll say here, just for the sake of it, it has 10 J.
Maggie: 10 J.
Barbara: Of magnetic potential.
Maggie: Then you push it.
Barbara: If we push it, we give it a little...
Maggie:...a little bit of kinetic.
Barbara: Of one, and as it gets closer and closer. Here, it would just have like 2, the 1 from the push and this, this distance was equal to 9 J, cause it speeds up and pulls it.
Cynthia: But.
Barbara: And this was 1.
(Trevor starts talking to himself about his answer.)
Barbara: So here, this was 2 and then it hits it with 11.
Maggie: Okay.
Barbara: Okay, so then...
Maggie: It goes to zero.
Barbara: It goes to zero and so transfers all the 11...
Maggie: ...to here.
Barbara: This one's zero cause it's touching.  This one we're saying is 9.
Maggie: So now it has.
Barbara: I would say it's just a teeny less than 9.
Maggie: Eleven plus nine, right?
Barbara: Well, the thing is, is I think it's just eleven.  This is what I was asking Trevor, and Trevor, would you look?
Trevor: Yeah!
Barbara: It hits with 11.  This is 9 going gravitat-, I mean magnetic.
Maggie: Pointing that way.
Barbara: Potential.
Trevor: But don't, you can't think of.
(Barbara is saying something about 11.)
Cynthia: You can't give a direction.
Maggie: Ugh, I miss forces.
Barbara: You can't?
Maggie: Okay.
Trevor: No, but it's, there's this invisible...
All at the same time: Cynthia: But force wouldn't explain this.
Maggie: I know, I know, I know.
Barbara: [...] Is it taking the 9 or is it adding to it?
Trevor: Let me just say.  If this ball moves this way, 9 has to go up, because the position is what matters to magnetic energy.
Between C and M: Cynthia: That's kind of the beauty of this force, unless the polarities could magically reverse.
Maggie: Right, yeah.
Cynthia: Yeah, let's not go there.
Maggie: Yeah.
Between T and B: Trevor: If this ball moves this way, that nine can add to something else.
Barbara: Oh, okay.
Trevor: Right, but it's...
Barbara:...Okay, so the eleven transfers.
Maggie: So eleven plus nine.
Trevor: No.
Maggie: No.  (Throws head back.)
Trevor: The total energy, yes.  The total energy will be twenty.
Barbara: Yet it's.
Maggie: But then what?
Trevor: How much of it is magnetic energy, and how much is kinetic?
Maggie: Nine is magnetic.
Barbara: So eleven's kinetic.
Maggie: And eleven is kinetic.
Barbara: And.
Trevor: Right, and as it moves away, the kinetic actually goes down...
Cynthia: ...and the magnetic increases.
Trevor: Because it's escaping the magnet.  You use some of that energy up to escape the magnet.
Cynthia: Right.
Maggie: Okay.
Cynthia: But, but..
Trevor: ...But not that much...
Cynthia: ...But it's compensated...
Barbara:...All your numbers [are at the top here?]...
Cynthia:...It's compensated by that increase of magnetic, right?
(Maggie is talking to Barbara, but I cannot understand her.)
Cynthia: So in a sense, we've...
Trevor: I don't understand what you're saying.
Cynthia: If it moves further away, then the magnetic energy has increased.
Trevor: Increased.

In this episode, I see Trevor bidding to be recognized as a science expert when:

• He offers to be video-recorded by Cynthia.
• He talks to himself as he writes out his answer.  The three ladies at his table are talking to one another, and I interpret this to mean that they are still working their answers out.  I interpret Trevor's talking out loud to himself as he writes to indicate to these three that he has already finished his answer (and, in a sense, doesn't need their help).
• He positions himself as the knower when he responds to Barbara's questions.

I see Trevor's group members recognizing him as a science expert when:

• Cynthia says, "Oh, THANK YOU, Trevor!" when he offers to be video-recorded.  The way she says it comes across as submissive (?) to me, as though she is so gratified that someone as smart as Trevor would give her his attention.  (I'm exaggerating a bit to make my point.)  Cynthia goes on to say that she can use the video of Trevor talking as 'proof that she was in a science class.'
• Barbara responds to Trevor's offer to be recorded by saying that "he will get it right," comparing his (anticipated correct) answer to hers (which she anticipates will be incorrect).
• Barbara asks Trevor to check her reasoning as she explains it to Maggie (positioning Trevor as an expert and both herself and Maggie as learners).

I'm not sure yet how these videos might inform theory about science identity, but I think they have potential!

Teachers Struggle with Goals for Student Notebooks

On Wednesday of Week 2, Lezlie deWater gave a guest presentation on student science notebooks in the afternoon of E2. It kicked off with a book club discussion of two articles, one on Inquiry (Science, May 2011) and one on Drawing (Science, Aug 2011). During the small group discussion of the Inquiry article, Debra and Madonna (along with Jean and Wendy) in Group 2 talk about their mixed feelings on notebooks and student thinking. Leslie Atkins has joined their table and offers her opinion as well. 

For the first 40 seconds of the clip, Debra talks about feeling obligated to have students use science notebooks ("I feel like I am married to the idea that you have to have a journal") since she feels it is her responsibility to prepare them for college or industry. Madonna jumps in at 0:50 to counter Debra, saying that it is "not only the minimum here (points to notebook) but then are we pushing the minimum in terms of mental exploration (gestures to head)". Leslie interjects, saying that in her mind the important thing is for students to communicate scientific ideas to each other, not keep a perfect ledger.
Madonna then changes tack from her earlier point (caring about mental exploration) and speaks about very high achieving students she has worked with who have terrible notebooks, and how it is difficult to work with these sort of people in industry. At the end of the episode, though, Madonna acknowledges that there is a tension with the notebooks:

[00:02:14.19] Madonna: There is kind of a play of both. There is something to be said for actually physically writing stuff down, but maybe we focus to much on the production.

Debra, in response to Madonna, references Leslie, and says:

[00:02:29.02] Debra: But what I think I hear you saying is that if we can get them nailed down on the skill of thinking, of being able to communicate their thinking, then it doesn't matter what format."


In this episode, Debra and Madonna alternatively emphasize the importance of student thinking while they also express concerns about preparing students in the structures and formatting they perceive is needed for college and future careers.  The questions they are struggling with seem to be: Do we need to prepare students to do formal scientific documentation that will be expected of them later on? Will teaching students to think and communicate be sufficient for them to be able to tackle any type of scientific documentation in the future? By focusing on formal structure in the notebooks, are we masking our assessment of students' actual understanding of the physics? Are science journals/notebooks necessary and if so, what style is best for my classroom?

Assessments and LABELS

E1 130808 822 T7

Assessment

Prior to this conversation there was a discussion on assessment and how we evaluate students. Cynthia spoke of the European model of students having to articulate what they know in front of the teacher/class.

This clip spoke to some common components/issues of standards and assessment. Probably the most fascinating part of the video for me was that Cynthia was identifying kids in 5^th grade as advanced and regular education.

Drawing IS Writing

These clips show moments in the class that Katie and I were very excited by when they were occurring, and both marked with so many flags that when Brad started talking, I accidentally wrote Blag and we both contracted a nearly terminal case of the giggles.

But--I'm not sure they're exciting as episodes per se--I don't know that I could really say "something interesting HAPPENED". I think they are exciting because the *ideas* that the teachers are communicating are exciting to us! I see these clips as showing us not the process of learning, but a demonstration of some of the learning that has occurred over the past several weeks.

It seems to me that the teachers are expressing that writing is not the only way, or even the best way, to represent an abstract idea. Akbar points out that drawing using symbols but so does writing, "so in a way, drawing IS writing." Julie takes it even further: "Drawing is even MORE abstract" and less prone to "BS-ing" using what Brad calls "the conventions of writing". I don't think it's a stretch to say that these views may have been influenced by the teachers' participation in energy theater, which uses ways other than written language to communicate ideas about abstraction. I also have felt the importance of escaping the "conventions of written language" over the past two weeks--I can see how when my students use words like "respiration" and "metabolism", it is too easy to assume that they mean what I mean when I use those words. Having students represent their ideas in other ways might give me--and them--a better insight into what they are truly thinking. This is a very powerful idea that *I* have learned over the past few weeks!

Transcripts
Clip #1
Akbar: With drawing, when you're learning something it's easier to see it...You see it here (gestures out, as if to a piece of paper) and then you see it here (gestures in). And then you're able to draw what you see. It's easier to see it than say it. And so writing is like saying it, and drawing is like seeing it. So sometimes it's easier to see it.(continues gestures) And then once you see it very well, now it's easier to say it.  Drawing is a good segue into writing, like a first line of defense, or first thing to do. Like BOOM--ok, I'm going to gather what I'm seeing in my mind's eye. And then from here, now, if you're able to talk about it...then it would be easier to put it into writing.  Drawing is real good tool...A lot of times kids are fearful of writing...say they may have language barriers or other things, and they may not have the right words to say it, or the appropriate words.  But drawing is almost universal, there's not like a Somalian eye or a Russian eye; we all see!

Clip #2
Akbar: So in drawing, basically, you use symbols, and in writing you use symbols, so in essence, so drawing IS writing.

Julie: ...more abstract way. I think as teachers...I think *I* have viewed kids drawing as sort of a cop out - they don't want to write. And somehow we think drawing is less academic, but in fact it really is MORE abstract...than BSing their way through...

Brad: There are fewer conventions in drawing. A lot of times kids have trouble writing because they have difficulty with all the conventions of writing, not the articulation of ideas in a cohesive fashion. And so it can be a cop-out--just like writing can be a cop-out. If you know the conventions, you can bullshit your way through something. Versus...you could cop out of a drawing as well, but the conventions of drawing, particularly when you're not given any requirements...it's just so raw that it frees you up to try things...I already have the vision, I just wanna get that vision out...F


Debra: The assessment of what they know is crippled by how they write. I'm assessing their thinking, not their writing. So to me...if you can draw it, and tell me about it, then I know you know it.

Boring: see civil engineers

Today, Stamatis brought up Count Rumford's experiment, which is often pointed out as empirical evidence that the caloric theory of heat (heat as a conserved sunstance-like quantity) was wrong. Rumford argued that you appear to be able to generate an infinite amount of heat by boring a hole in an object. Therefore heat cannot be a finite substance-like thing that is stored in objects. The competing theory was that heat is a kind of motion, which later was incorporated into thermodynamics.

Well, this reminded me of the classic UK yellow pages entry in the 90's: "Boring: see civil engineers":

http://www.apnewsarchive.com/1996/Civil-Engineers-No-Longer-Boring-Yellow-Pages-Says-So/id-fbef506d8ad666d913ccdd5588c7e698

ATP: An electrical impulse thing and a little zap

This is more on the theme of “getting hot while dropping your balls.”  As a refresher, in E1 on Monday morning (8/12/13), the class began the day by drawing diagrams for the two scenarios considered the previous Friday: raising a bowling ball at constant velocity and lowering the ball at constant velocity.  The group I am considering in this episode is: Jeff (in blue), John, Sara (in green), and Emma.  In the first half hour of class, they drew a diagram representing the energy theater.

Their diagram includes instances of chemical energy converting to thermal energy, and they recognize this as a process that includes ATP, but they do not know how to account for it.  Now that they have finished, Adam comes to the table to check on them and see how they are doing.  What follows is a discussion regarding what they think about the scenarios they have just looked at. 

I love that each member of the group had a chance to weigh in on the matter, even Sara who is typically rather quiet.  To each of them, the processes involved in going from chemical energy (ATP) to muscle movement to thermal energy, are a mystery, and each of them has a different way of expressing their befuddlement.  Jeff at 0:13 says “I need to scratch my head and go wow.”  John, at 1:13, adds “It gets super fancy, which I don’t even want to get into.”  Even one of the instructors, Adam, can’t hold back his relationship with biology at 1:25.  “I’m a physics guy, so when I hear ATP I kind go…” and he apparently makes a face or a twitch or something. 

At 2:14, Sara enters in and continues off of John’s wonderment at “an electrical impulse thing” and “a little zap that we’re not accounting for.”  She wants to keep separate the energy story and the processes of ATP.  “The electrical is part of the chemical.”  She sees that for kids, it wouldn't make sense to have chemical go to electrical and so on.  Emma fleshes this out with a long montage of chemical to electrical to new chemical to new electrical.  Without even knowing the exact process, she sees the weaving that might happen.  “Having a separate story, I think, is a good thing,” she adds at the end.

Finally, at 2:54 Sara suggests, “I don’t think understanding this way is a misconception.”  This is an interesting way to phrase her idea.  I wonder how she thinks of physics and biology misconceptions.  Beyond that, what is clear to me here is that all four teachers agree that energy theater shouldn't (and maybe even can’t) address all of the steps that may exist as chemical energy transforms to thermal. 

“If you don’t understand where the energy comes from, call it chemical.”  This is quite common in physics.  I certainly do this in my classes with the simple examples I use that might need such a designation, such as a car driving or a person pushing an object.  Honestly, I've rarely made an attempt to develop a picture that is deeper than this.  It is fascinating to watch a group of people attempt to dig at this deeper picture and essentially come up baffled and prepared to stick with “chemical to thermal, let’s move on.”  I wonder if this might be a valuable class exercise for my students.  Let them struggle to build a more complex picture, to give them a greater appreciation for hiding some details in their energy representation.

Full video: E1 130812 0814 T6-1

Debunking the assumption that "giving students the right answer shuts them down."

I am particularly interested in what happens when an instructor gives the participants "the right answer" and the participants recognize that this is happening.  I became interested (last summer) for two reasons:

1. I noticed that sometimes 'getting the right answer' promotes really productive conversations, whereas I think our community often assumes that 'getting the right answer' will shut students down.
2. I noticed that in cases in which 'getting the right answer' seems to shut participants down, I can look at the situation and see clues about why that might have happened.  (For example, participants communicate the expectation that the answer should be simple, whereas the answer is actually quite complex and/or takes a long time to communicate.)

Someone (Stamatis?) mentioned to me that Rachel had given a 'mini-lecture' in E2 and that they had caught an interesting conversation about Julie's experience of the lecture on tape.  So I clipped it!

Context: The first clip below shows the moment that the participants communicated to Rachel that they wanted an answer:

Teacher (in background): [Can you say if gravity is different than pressure?]
Rachel: Yes, gravity is different than pressure.
Teacher: Gravity is different from pressure, okay.
Rachel: Yes, Deb.
Debra: Would this be a time where you might just say, 'Okay, in the scientific community, this is what blah blah blah.'
Rachel (laughing): Debra is making a suggestion [...].
Debra: Can we just get the answer, yeah. (laughter)

I'm actually not sure which question they are asking Rachel to answer, but, for the next 10-15 minutes, Rachel shares her answer to this question and others that teachers ask intermittently throughout.

My best reconstruction is that the teachers have just done 'particle theater' (like energy theater, but tracking the matter through the system, rather than the energy) for the 'two-piston scenario.'  In this scenario, there are two equal-temperature (equal-N) pistons of gas side by side.  The gas in one of the pistons has been compressed more than the other.  In past iterations of this scenario, the participants have been asked which of the pistons will push a block further when released.  (Abby or E2 folks, am I getting this right?)

Rachel begins her lecture by discussing whether or not there is potential energy in the gas (that is inside the compressed pistons).  She says that if there were PE in the gas, it might be like particles 'squishing' when they bump into one another (in particle theater).  She says that she was raised to believe that the atoms of a (ideal) gas in fact are not squishy, although she acknowledges that if they were talking about a real gas, things would be different.

She goes on to say that another thing she was raised to believe is that gas particles are mostly in empty space, so that most of what happens is free travel between the walls of the container (as opposed to many collisions between gas particles).  In the smaller (more compressed) container, the number of collisions increases, and we (not sure if she means the teachers or the scientific community) conceptualized that as pressure.  She explains that each "bonk" exerts a push, and pressure is more like a push than an energy, even though pressure and energy are not unrelated.  She says that pressure hasn't been represented in either particle or energy theater.

Mary then interjects a question: If you were trying to show the difference between the more-compressed and less-compressed pistons in energy theater, would the difference be in the rate of transfer of energy?  Rachel responds that she thinks the difference would be in amount transferred, rather than how fast the transfer happened.  She says she'll have to think about the rate thing, but she's not ready to do that on her feet.  She draws the ETD below (including only air in chamber, piston, and block boxes), explaining her thinking as she goes:

She tells the teachers that there are the same number of Ts in the gas in the less- and more-compressed cases.  The Ts transform into Ks in the piston and are then transferred to the block.  In the more-compressed case, more Ts transform to Ks.  This accounts for it getting colder in the more-compressed case.  She states that this explanation does not account for the springiness in the two pistons, and it would need to.

Rachel also shares the reason that the instructors gave them this scenario: the two pistons are similar in many ways -- they have the same amount of energy to start -- but one transfers a lot of its energy.  In life, we want to move the block more, and the instructors would like the participants to be able to understand what it is about a scenario that gives us the opportunity to move the block more.  Rachel ends by saying that she feels "completely nude" because she gave them a ton of answers as well as the instructors' reason for asking them to think about this scenario.

Debra then requests that Rachel add the hand and the piston to her diagram for the more-compressed scenario.  (You can see that she does in the picture above.)  Rachel begins to talk through what this adds: There are Cs in the hand, Ks in the hand, Ks in the piston, etc.  Debra asks Rachel if the same number of Ks go into the piston for both the less- and more-compressed cases.  Rachel points out that she has to leave time for the system to come to equilibrium, since the hand that compresses the piston more is going to add more Ts, whereas Rachel has said that both pistons start with the same number of Ts.  (So she has to wait for the excess Ts to leave the system.)  Debra responds that this is confusing, and Rachel agrees.  They briefly discuss whether the Ts that are in the gas/air come from (did all of them come from the hand, or were some already in the gas?). 

Rachel instructs them to write in their notebooks silently for ten minutes.  The clip below starts just after this writing time.  Rachel approaches the table with (CCW from right) Julie, Don, Gail, and Jean.  Rachel sheepishly admits that she's not used to giving away answers, Julie responds by saying that she wasn't paying attention, Rachel leaves the table, and Julie and Don discuss the scenario in more depth.  Watch and enjoy!

Participants' response to 'getting the right answer':

Rachel: I never did that before [...].
(Julie laughs.)
Julie: What, just said straight out?
Rachel: Yeah.
Julie: You know what's funny is that I actually, my brain sort of turned off.  Which is probably why we say that's what we want but we don't actually want that.
Rachel: Mmhm.
Julie: Cause then I was like, 'Well, I don't agree with that cause we just did all this.'  And so what?  It doesn't have any meaning for me.
Rachel: Yeah.
Julie: And so I'm glad that...
Rachel: And [meanwhile] I just stand up there and you guys are like (stares off).
Julie: (Making noise and pretending to write something down.)  Yeah, writing it all down.  Totally.
Rachel laughs.
Rachel: Sorry [...] (walks away)
Don: For me, when she, see I needed to see those Ts go over, and once those Ts went over, and I saw that the energy was the same, then I started writing, cause that was the piece that I wasn't getting.
Julie: Wait, say, I'm...
Don: Well, do you see how there's 5 Ts in both.  See, the energy is the same in both of those...
Julie:...I agree...
Don:...The thermal energy is the same whether it's compressed or not, and that's what these guys were saying at the very beginning, and I wasn't agreein' with it.  And so as soon as we saw that transfer, and there was more energy was transferred...
Julie:...Oh I see, I see...
Don:...Then I was able to start to put this thing together.
Julie: And what was your, what's your thinking as to why more energy transferred?
Don: Why did more energy transfer? (Pause) Huh! (Laughs)
Julie: Right?
Don: Why did more energy transfer?
Julie: And then that's when we get confused with the force story because we say, "Pressure!"
Don: Yeah.
Julie: And pressure is a force and we can't say it.
Don: Right.  The reason why more energy transferred is more energy was put into it by the hand to begin with.
Julie: But we just said there's five Ts in both.
Don: Right.  You're right.  Never mind.
Julie laughs.
Julie: Do you see what I'm sayin'?  We still don't know.
Don: I know.  Then you get to that point when you can't. 
Julie: Yeah.
Don: It's like what do you do with it?
Julie: Right.
Don: Then you have to bring in particle theory.
Julie: Right, cause we both, we both got to a place where we can say, 'In the more compressed, more thermal is converted to movement, kinetic.'
Don: Mmhm.
Julie: And then we're good.  But then if we actually take that a step...
Don:...Yeah...
Julie:...Deeper.
Don: What causes the transfer?...
Julie:...Right...
Don: ...The number of hits per unit of time?
Julie: Right, which we don't even know what that really mean.  I mean, it doesn't mean a whole lot yet.
Don: Yeah, it's just like the drummer.  (Hits the table quickly, makes high-frequency noise:) Brrrrrr. Versus boink, boink, boink (hits table more slowly).
Julie: Except we said instead of it going boink, boink, boink, boink (hits table slowly, same-strength hits), it was actually like (hits table at different frequencies with different strengths).
Don: Yeah, all sorts of different random. 
Julie: Yeah, right.
Don: But if you look at it as a whole, it's more.
Julie: The take-away for me, it's mind-blowing to think that the speed didn't, that the change in speed wasn't necessarily directly related to the pressure component.  That it was more about collisions than it was, directly speaking.
Don: Mmhm.
Julie: There had to be like that half-step in between, you know?
Don: Yeah because we saw that the speed was the same in both of these, it wasn't about the speed, it was just the number of, more collisions more frequently.

What I see in this video: My interpretation of what is happening in this video is that:

1. Julie says she immediately tuned out when Rachel started giving her answer.  She attributes this to her disagreeing with Rachel's answer in light of her own thinking, so that Rachel's answer "didn't have any meaning for her."  I'm not sure whether she means that Rachel was answering a question that she did not have, whether she disagreed with Rachel's answer (and thus did not value it, although this doesn't seem right to me knowing Julie), or if she could not connect Rachel's answer to her own and so lost interest. 
2. Don, on the other hand, says that Rachel's answer responded to a 'need' that he had.  He says that (part of) Rachel's answer matched what another group said that he originally disagreed with.  It's not clear to me whether Rachel's authority convinced him, or whether she filled in a missing piece for him that made the other group's answer sensible.  (I'd guess the latter, because he points to a specific piece of Rachel's explanation that helped him to "put this thing together.")
3. Julie then asks Don a question about mechanism -- why does more energy transfer?  I LOVE Don's response.  His tone and facial expression when he says "Huh!" suggest to me that he is amused that he thought he got it but now recognizes that there is more for him to understand.  Julie and Don then engage in a beautiful discussion about why the more-compressed case transfers more energy.  Although they hedge a lot, their answer is mechanistic and thoughtfully negotiated: there are more collisions in the more-compressed case than in the less-compressed case.  I see so much physics in what they say: they negotiate that it can't be speed of the particles, since the two gases are the same temperature, so it must be the frequency; they use their fists to communicate how the strength and frequency of the collisions is different in the more- and less-compressed gases, and Julie (oh, Julie!) points to a distribution of strengths (speeds) and frequencies (Maxwell distribution, anyone?); and they reflect on the limits of their understanding as they go.

I can't decide whether this clip is an example of the answer 'shutting students down' or not.  On the one hand, Julie admits that she stopped listening when Rachel started 'lecturing,' and Don accepted the 'answer' without pushing for mechanism.  On the other hand, Don's noticing what he learned from Rachel's answer inspired Julie's question, which began this lovely exchange.  I think this would require more careful study -- including understanding what happened around this conversation -- so I'm flagging it for future reference.