Reducing Circuits: Solve for Everything, Everytime

With circuits this year, I’ve been teaching a “solve for everything” approach that balances circuit reduction with reasoning about Kirchoff’s rules. First students reduce the circuit and then work to determine the current, potential differences, and power outputs of each device.

For example, on the student whiteboard below, they were supposed to find the power output at Resistor Three. I’ve been pushing for solving for the power input/output of everything, so they can check energy conservation.


I worried about teaching them to use the table, that maybe it would turn it into a mindless numbers game, but the organization actually allows students to spend energy on reasoning for how currents / potential differences should relate. It also just helps with the book-keeping so keeping track of what they know and don’t know easy. It also makes checking work easy. The first two columns should multiply to the third column by Ohm’s Law. And the 2nd and 3rd columns should multiply to the 4th column by the power relationship. A colleague of mine extended my table method to include all the equivalent resistors along the way as well.

Overall, I’m pretty happy with this approach. One tweak I would make would require them to write/diagram their reasoning about how the Kirchoff’s reasoning–either in algebra or using the diagrams.

Broadening Participation Research in PER: A Slightly More Comprehensive Look

I really enjoyed reading and thinking about this post: What Computing Education Research does that Engineering Ed and Physics Ed Research doesn’t

One of the claims put forth in the post is the Computing Education Research (CER) community seems to have more lively and stronger focus on broadening participation than either the Physics Education Research (PER) of Engineering Education Research (EER) communities. From that post:

“Carl [Wieman] said that gender diversity just wasn’t a priority in PER. I dug into the PER groups around the US. From what I could find, he’s right. Eric Mazur’s group has one paper on this issue, from 2006 (see here). I couldn’t find any at U. Washington or at Boulder. There probably is work on gender diversity in physics education research, but it certainly doesn’t stand out like the broadening participation in computing effort in the United States.”

I thought I would dig a little deeper, and do just a quick survey of all articles published in Physical Review–Special Topics in Physics Education Research, which touched upon gender, participation, or highlighted international research. I should note that the list below is based on titles only–I didn’t read the abstracts or the papers. While this isn’t a thorough analysis, it paints a slightly less bleak picture than one paper published almost a decade ago.

Note: I’m certainly not looking to pick a fight about PER vs. CER or EER. I feel much like the author of the post, who writes:

I don’t have a deep bottom-line here… My exploration of EER and PER gave me a new appreciation that CER has something special. It’s not as big or established as EER or PER, but we’re collaborative, international, working on hard and important problems, and using a wide variety of methods, from in-classroom to laboratory studies. That’s pretty cool.” 

The authors post has made me pause to think about our priorities and prodded me to dig a little deeper into the data to see what the situation is beyond just trusting Carl’s Wieman’s comment and a quick examination of just two research groups.

Note 2: I also added relevant presentations from most recent PER Conference.

Gender Studies

Gender gap on concept inventories in physics: What is consistent, what is inconsistent, and what factors influence the gap? Adrian Madsen, Sarah B. McKagan, and Eleanor C. Sayre Phys. Rev. ST Phys. Educ. Res. 9
Comparative analysis of female physicists in the physical sciences: Motivation and background variables .Katherine P. Dabney and Robert H. Tai Phys. Rev. ST Phys. Educ. Res. 10, 010104 (2014) – Published 3 February 2014
Female physicist doctoral experiences Katherine P. Dabney and Robert H. Tai. Phys. Rev. ST Phys. Educ. Res. 9, 010115 (2013) – Published 10 April 2013
Factors that affect the physical science career interest of female students: Testing five common hypotheses. Zahra Hazari, Geoff Potvin, Robynne M. Lock, Florin Lung, Gerhard Sonnert, and Philip M. Sadler. Phys. Rev. ST Phys. Educ. Res. 9, 020115 (2013) – Published 22 October 2013
Preliminary investigation of instructor effects on gender gap in introductory physics. Kimberley Kreutzer and Andrew Boudreaux. Phys. Rev. ST Phys. Educ. Res. 8, 010120 (2012) – Published 4 May 2012
Gender disparities in second-semester college physics: The incremental effects of a “smog of bias” Lauren E. Kost-Smith, Steven J. Pollock, and Noah D. Finkelstein. Phys. Rev. ST Phys. Educ. Res. 6, 020112 (2010) – Published 3 September 2010
Characterizing the gender gap in introductory physics Lauren E. Kost, Steven J. Pollock, and Noah D. Finkelstein. Phys. Rev. ST Phys. Educ. Res. 5, 010101 (2009) – Published 8 January 2009
Gender differences in the use of an online homework system in an introductory physics course Gerd Kortemeyer Phys. Rev. ST Phys. Educ. Res. 5, 010107 (2009) – Published 26 May 2009
Reducing the gender gap in the physics classroom: How sufficient is interactive engagement? Steven J. Pollock, Noah D. Finkelstein, and Lauren E. Kost. Phys. Rev. ST Phys. Educ. Res. 3, 010107 (2007) – Published 5 June 2007

Participation Studies

How do they get here?: Paths into physics education research Ramón S. Barthelemy, Charles Henderson, and Megan L. Grunert. Phys. Rev. ST Phys. Educ. Res. 9
Physics teachers’ perspectives on factors that affect urban physics participation and accessibility Angela M. Kelly. Phys. Rev. ST Phys. Educ. Res. 9, 010122 (2013) – Published 19 June 2013
Educational trajectories of graduate students in physics education research . Ben Van Dusen, Ramón S. Barthelemy, and Charles Henderson. Phys. Rev. ST Phys. Educ. Res. 10, 020106 (2014) – Published 21 July 2014
Toward equity through participation in Modeling Instruction in introductory university physics
Eric Brewe, Vashti Sawtelle, Laird H. Kramer, George E. O’Brien, Idaykis Rodriguez, and Priscilla Pamelá. Phys. Rev. ST Phys. Educ. Res. 6, 010106 (2010) – Published 20 May 2010

International Studies

Secondary implementation of interactive engagement teaching techniques: Choices and challenges in a Gulf Arab context G. W. Hitt, A. F. Isakovic, O. Fawwaz, M. S. Bawa’aneh, N. El-Kork, S. Makkiyil, and I. A. Qattan. Phys. Rev. ST Phys. Educ. Res 10, 020123 – Published 6 October 2014

Introduction of interactive learning into French university physics classrooms Alexander L. Rudolph, Brahim Lamine, Michael Joyce, Hélène Vignolles, and David Consiglio. Phys. Rev. ST Phys. Educ. Res. 10, 010103 (2014) – Published 27 January 2014

Validating the Japanese translation of the Force and Motion Conceptual Evaluation and comparing performance levels of American and Japanese students Michi Ishimoto, Ronald K. Thornton, and David R. Sokoloff. Phys. Rev. ST Phys. Educ. Res. 10, 020114 (2014) – Published 19 August 2014
Effectiveness of Tutorials for Introductory Physics in Argentinean high schools J. Benegas and J. Sirur Flores. Phys. Rev. ST Phys. Educ. Res. 10, 010110 (2014) – Published 24 March 2014
Introducing Taiwanese undergraduate students to the nature of science through Nobel Prize stories Haim Eshach, Fu-Kwun Hwang, Hsin-Kai Wu, and Ying-Shao Hsu. Phys. Rev. ST Phys. Educ. Res. 9, 010116 (2013) – Published 25 April 2013
Student effort expectations and their learning in first-year introductory physics: A case study in Thailand U. Wutchana and N. Emarat. Phys. Rev. ST Phys. Educ. Res. 7, 010111 (2011) – Published 24 June 2011


Validation study of the Colorado Learning Attitudes about Science Survey at a Hispanic-serving institution Vashti Sawtelle, Eric Brewe, and Laird Kramer Phys. Rev. ST Phys. Educ. Res. 5, 023101 (2009) – Published 28 August 2009

Presentations at 2014 PER Conference:

Exposure to underrepresentation discussion: The impacts on women’s attitudes and identities by Geoff Potvin, Zahra Hazari, Robynne Lock

Female Students’ Persistence and Engagement in Physics: The Role of High School Experiences by Zahra Hazari, Eric Brewe, Theodore Hodapp, Renee Michelle Goertzen, Robynne M. Lock, Cheryl A. P. Cass

The Impacts of Instructor and Student Gender on Student Performance in Introductory Modeling Instruction Courses by Daryl McPadden, Eric Brewe.

The Long Term Impacts of Modeling Physics: The Performance of Men and Women in  Follow-on Upper Level Physics Courses by Idaykis Rodriguez, Eric Brewe, Laird H. Kramer.

The Experiences of Women in Post Graduate Physics and Astronomy Programs: The Roles of Support, Career Goals, and Gendered Experiences by Ramon Barthelemy  Melinda McCormick, Charles Henderson

Discussing Underrepresentation as a Means to Increasing Female Physics Identity by Robynne M. Lock , Zahra Hazari, Reganne Tompkins

Exploring the gender gap in one department’s algebra-based physics course by Twanelle Walker Majors, Paula V. Engelhardt, Steve J. Robinson

Race and Gender and Leaving STEM: Preliminary Results of The Roots of STEM Project by Melissa Dancy  Elizabeth Stearns, Roslyn Mickelson, Stephanie Moller, Martha Bottia

Concluding Comments:

I’m not sure what this mean, if anything yet, but that’s what I did this morning. Making this list doesn’t prove anything about our fields priority in these matters–we’d have to look at funding, impacts, white papers, etc. But for me, it’s a beginning in looking into it

If you feel I missed an important Physical Review paper or PERC 2014 presentation, let me know in the comments.

Logic and Reasoning– Tools for Empowerment or Coercion?

We just came into that week in Physics Licensure–the week where students start asking, “Did I learn anything in Physics I?”

As I’ve talked about before, Physics Licensure I and II are very much a band-aid sequence of courses for our future physics teachers–helping students to develop the reasoning skills and conceptual understanding they didn’t have much opportunity to learn our introductory physics sequence.

Students are really struggling with reasoning about Newton’s Laws. The course, being a band-aid, isn’t really providing the right kind of opportunities either. We go through tutorials each week, students do tutorial homework, and they have to write brief reflections each week. In addition they work some AP physics problems, and they have to make ongoing concept map to make connections among what they are learning. In all that, students get a fair amount of practice building concepts and reasoning, but they don’t get enough opportunity to explore and grapple with actual phenomena.

We’ve encountered many days where students seem to follow along with a guided line of reasoning stemming from Newton’s Laws (not easily).  At the end of it, someone will say, ‘That makes no sense”. In that, they are understanding and can produce the logic of the argument, about how if N2nd Law and N3rd law are true, it implies that some other conclusion must be true. To students, N2nd and N3rd law are not ideas they “own”; they aren’t using these ideas to discover puzzling implications about the world. Rather, the guided reasoning they are asked to follow coerces them into concluding things they’d really rather not say and definitely don’t believe. They aren’t happy about it.

My sense as a instructor is that many of our students still largely think that force is in the direction of motion, that you have to push harder than friction (or up against gravity) to keep an object moving steadily, that pushing harder will result it moving faster. Sure, you can remind them of Newton’s 2nd Law, and they can be coerced into saying something more correct, but it’s definitely coercion.

That’s how we’ve gotten to the place where students are saying, “I think I learned nothing in Physics I”. These students need a lot more experience with phenomena and grappling with their own ideas, the ideas of each other, etc. Right now, I don’t think I’m providing what they need.

Aggregating Three Posts on Research (and the FCI)

I’ve written a few posts about research (and the FCI) that I’d like gather in one place:

Physics Education: Research, Assessment, and Poverty

Disaggregating Learning Gains

Standards of Reporting FCI Data

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