## Introductory Physics for In-Service Teachers

**Matter & Interactions:**

*A modern course in physics for high school teachers*

**Note added Summer 2018**: This class is now being instructed by Dr. Brand Fortner (email).

Please click here for Dr. Fortner's webpage.

*Matter & Interactions* is a modern two-semester physics curriculum and textbook developed by Prof. Ruth Chabay and Prof. Bruce Sherwood, emeritus professors in the Department of Physics at NCSU. PY 581/PY 582 are distance learning versions of the *Matter & Interactions* curriculum designed specifically for in-service high school physics teachers. Mechanics is often taught in the spring semester and Electricity and Magnetism in the fall semester or in summer session II. While the recommended sequence is to start with mechanics, physics teachers have found it possible to take electricity and magnetism first if they have a strong physics background and good calculus skills. The intent of this course is not to train teachers in how to teach this college-level curriculum in high school but rather to enhance teachers' physics culture, by offering a broad, deep, and contemporary approach to physics which can enhance their approaches to their own teaching. 20th century physics and a contemporary perspective are integrated throughout the curriculum. This course will be of particular interest to any teacher interested in new insights into contemporary physics and novel physics pedagogy.

**A Modern Perspective on Calculus-Based Introductory Physics**

*Matter & Interactions* emphasizes a modern perspective on the calculus-based introductory physics curriculum taken by engineering and science students. It engages students in:

-Starting analyses from fundamental principles rather than from secondary formulas.

-Making macro-micro connections, based on the atomic nature of matter.

-Modeling physical systems: making idealizations, simplifying assumptions, estimates.

-Constructing computational models to predict the time evolution of system behavior.

**Volume 1: Modern Mechanics**

*Modern Mechanics* focuses on the atomic nature of matter and integrates traditional mechanics with thermal physics to provide a coherent and contemporary perspective on the subject. There is strong emphasis on a small number of fundamental principles: the Momentum Principle (Newton's form of Newton's second law), the Energy Principle (which subsumes the first law of thermodynamics), the Angular Momentum Principle, and the fundamental assumption of statistical mechanics, which leads to the second law of thermodynamics. The ball-and-spring model of solids plays a crucial role. Photon emission and absorption in quantized systems is included.

**Volume 2: Electric & Magnetic Interactions**

*Electric and Magnetic Interactions* builds on the atomic nature of matter and the treatment of electric force and energy in *Modern Mechanics* with the addition of the field concept, Maxwell's equations, and the role of electrons in conductors and insulators. A thorough treatment of the effects of fields on atomic matter makes it possible to unify the analysis of electrostatics and circuits. The climax is the classical interaction of light and matter, followed by a discussion of the contrast between this wave picture and the photon picture previously developed in *Modern Mechanics*.

**Fundamental principles:** Physicists place great emphasis on the *reductionist* nature of their science, that starting from a few powerful fundamental principles such as the energy principle one can analyze a very broad range of complex real-world phenomena. Despite this shared viewpoint, most physics curricula inadvertently encourage students to view the subject as one in which there is a huge number of special-case formulas, one for each specific situation. As a result, students come to believe that their task is to plug given numbers into specified formulas, and they rarely encounter a problem that hasn't already been worked out in detail for them in the textbook. In contrast, *Matter & Interactions* strongly emphasizes starting all analyses from fundamental principles, thus empowering students to attack novel situations, not just plug numbers into known solutions.

**Atoms:** The atomic nature of matter is constantly emphasized throughout the curriculum, and macro-micro connections are continually made. In addition to its intrinsic interest and importance, the emphasis on atoms facilitates integrating subjects that are usually kept completely separate. In the first semester, mechanics and thermal physics are intertwined, culminating in a completely accessible application of quantum statistical mechanics to the thermal properties of solids. In the second semester, electrostatics and circuits are unified thanks to an atomic point of view that makes it possible to understand with a deep sense of mechanism the behavior of DC and RC circuits, analyzed directly in terms of Coulomb's law, and the properties of conductors.

**Modeling:** In *Matter & Interactions* students encounter messy real-world situations to be analyzed by making a simplified physical model of the phenomenon, through approximations, simplifying assumptions, idealizations, and estimates. Such physical modeling is at the heart of contemporary physics but is nearly absent from most curricula, which unfortunately contributes to shaping student beliefs that physics is not applicable in the real world.

**Computation:** It used to be that physics could be characterized as experiment, theory, and their interplay. However, contemporary physics is experiment, theory, computation, and their interplay. Yet even someone with an undergraduate degree in physics may never have done any serious computational physics. In *Matter & Interactions* even those with no prior experience in programming quickly learn to write programs which produce navigable 3D animations, thanks to the novel VPython programming environment. For example, early in the mechanics semester students model a binary star system, with elliptical orbits. Early in the electricity and magnetism semester students write programs to visualize in 3D the electric field of a point charge, and of a dipole. After taking this course teachers will have the skills necessary for writing 3D programs to use for demonstration purposes in their own teaching.

**Experiments:** Experiments are integrated into the curriculum, often using very simple apparatus, with emphasis on contributing to conceptual development of the subject. The second semester features a desktop experiment kit with which it is possible to do electrostatic, circuit, and magnetism experiments at home.

**Course format:** The course is delivered in collaboration with DELTA, the distance learning branch of NCSU. Video lectures provided on DVD's include interactive elements in the form of questions to be answered by the viewer during the lecture, just as students responded in the original lecture by using electronic response systems. WebAssign is used for homework assignments, and an online forum brings participants together on a daily basis.

Comments from some recent students of the class:

*"Overall this is an outstanding course and I would recommend every high school physics teacher to take it. I love the computational aspect of the course, the micro/macro connections and the reliance on a handful of fundamental principles that keep popping out throughout the text. I have already noticed changes in my own teaching due to things I've learned in this course." *

*"To other teachers considering this course, it was huge in promoting my understanding of how E&M all fits together. The course made fields, potential, circuits and magnetism, and then EM radiation, make more sense than it ever has to me. It was amazing to me how we were still using the same techniques and concepts we learned the first couple weeks in completely new contexts to apply to electromagnetic radiation. This was my first experience with a completely-online course, so I wasn't exactly sure what to expect or how things would work, but I have to say it's been effective." *

*"As far as 1 course to get an overall deep understanding of not just the math but the actual concepts this would be the one." *

*This course made me understand electricity and magnetism more completely than any other class I have taken.
If I had to pitch this class to other teachers I would tell them that this class explores ideas in way that I have never seen presented before and really tries to connect many topics together that always seemed to be a disconnect for me. I think this class taught me a lot about myself and has also helped me to be a better teacher." *

*"For me and other folks, distance learning is our only avenue to enroll and complete a college course. Attending a traditional face-to-face course is nearly impossible due to everyday responsibilities. Again, the structure and design of this course created an enjoyable learning experience of an interesting subject." *

*"This course truly shows you how important foundational concepts are in developing a deeper understanding of more advanced physics content. The field approach of this text has truly changed my view of how electricity and magnetism should be taught to students." *

*"One of the most striking aspects of the course was its cohesiveness." *

*"I loved the programming aspect of the course (581 as well), so I'd advertise the fact that you'll be able to write code for really cool simulations that you can use with students. Take the charged particle in a B field; it's one thing to talk about a circular/helical path and it's quite another to actually observe it in python. Great feature, which I plan to use this spring in E and M..." *

*"I would recommend this course to other teachers. I was a little nervous coming into this course, being a chemistry major and not having a strong physics background, but the support received from the forum helped with any questions that I had. Also I think this is one of the best textbooks at explaining the material and giving plenty of example problems." *

*"This class has provided a framework and timeline for studying second semester physics topics at a depth that I would not have achieved otherwise. My aim was to sharpen my skills in topics where I knew I was rusty, and I believe that this goal was absolutely achieved in taking the 581-582 sequence. The class is a model for online courses, the most challenging and rewarding that I've come across. I feel more confident in my ability to teach and discuss topics that I did not before I took the class."*

*"The physics concepts covered in this class are complex, and make more sense (to me) when revisited and studied over time. Even if a teacher has taken E&M before, it's useful to take this course to refresh the material and to approach the material from a different direction. Even though I have taken E&M before, I felt like this course offered a fresh new perspective. I feel more confident with my own understanding of the material."*

*"I think this class would be very good for teachers who did not have a rigorous physics course in college, or those who are looking at teaching at the AP level. It is essential to have a good working knowledge of high-level physics, even to be able to teach at the high-school level. Also, this course does present a slightly different perspective than the typical physics course, and it is helpful to be able to see concepts from many different angles. Not all students think alike." *