I can see the point both in Bruce's and John's argument. Let me first take a look at Bruce's point of view. It was an enjoyable experience to read about the surface charge theory for the first time over a decade ago. It certainly helped me to achieve a fuller understanding on what is possibly going on in a simple DC circuit. I think that we all can agree that it is desirable, even crucial, that a teacher knows more than is absolutely needed in introductory physics. In fact, Bruce's and Ruth Chabay's work made an impact on Finnish physics education. A friend of mine did his PhD dissertation on teaching E&M using the surface charge theory as one component in a university course for physics majors. Some of these ideas even made their way in one HS physics textbook (it is more like optional reading).
Indeed, this approach has the virtue of creating unity between static electricity and DC circuits. It had bothered me for some time how we first taught electricity and then moved on teaching DC dircuit with only little real overlap. It also seemed to contribute to rote learning reducing physics into an exercise on elementary mathematical rules. Now I do thing differently. I demand both reasoning and ability to analyze DC circuits mathematically. In addition, I try to establish links between charge distribution, electric field, potential and DC circuits, although I do not explicitly teach the surface charge theory to my HS students. This striving for achieving some coherence is thanks to my exposure to Bruce's and Ruth's work.
Now turning to John's point of view. It seems plausible that the surface charge theory does not necessarily help in solving DC circuit problems. It is also easy to believe that an introductory physics treatment cannot possible go very deep into making use of the surface charge theory in the quantitative sense.However, I suppose that students in the U.S. have already done some ground work in DC circuits in HS? If so, it might be appropriate to introduce some idea on the mechanism how electric field is created in a simple DC circuit. This would be consistent with the sound spiraling approach advocated by John. Moreover, perhaps college/university students can appreciate the coherence and unity M & I approach can provide? It is then a judgement call how much time and effort should be devoted in creating this coherence.
Another interesting aspect related to DC circuits is how energy is transferred from a battery to a light bulb or whatever. There was an interesting AJP paper on this by Galili & Goihpark <http://www.ippp.dur.ac.uk/~davis/EnergyTransferElectricCircuits.pdf>. The paper makes use of surface charge model.
Just my two cents.
Antti
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