I’m combining two weeks in this post. The first week, we dealt with magnetic forces. One thing that I have never thought much about is the fact that the quantity is effectively an electric field, but one that depends on velocity. When velocity is involved, reference frames are involved, and that of course means Einstein […]
Read More Matter & Interactions II, Weeks 13 and 14We’re hanging out in chapter 19 looking at the properties of capacitors in circuits. In response to my (chemist) department chair’s accusation that I’m not rigorous enough in my teaching of “the scientific method” as it’s practiced in chemistry, I just had “the talk” about “THE” scientific method with the class and about how it […]
Read More Matter & Interactions II, Week 12More with circuits, and this time capacitors, and the brilliantly simple description M&I provides for their behavior. In chapter 19, we see that traditional textbooks have misled students in a very serious way regarding the behavior of capacitors. Those “other” textbooks neglect fringe fields. Ultimately, and unfortunately, this means that capacitors should not work at […]
Read More Matter & Interactions II, Week 11Chpater 18. Circuits. You don’t need resistance. You don’t need Ohm’s law. All you need is the fact that charged particles respond to electric fields created by other charged particles. It’s just that simple. When I took my first electromagnetism course, I felt stupid becuase I never could just look at a circuit and tell […]
Read More Matter & Interactions II, Week 10This week was a very short week consisting of only two days. We met as usual on Monday, but Tuesday was a “flip day” and ran as a Friday. This class doesn’t meet on Fridays so we only had one day this week, and we devoted it to tying up loose ends from chapter 17. […]
Read More Matter & Interactions II, Week 9This week was devoted entirely to programming for chapter 17 on magnetic fields. At least two students had difficulties with lists, which was surprising they’d used them in a previous chapter. It was like they’d never seen them before. Must be something in the water. Next week is basically a waste of time because thee […]
Read More Matter & Interactions II, Week 8This week, I was away at the winter AAPT meeting in Atlanta. Students began working on the experiments from chapter 17, which serve to introduce magnetic fields. I want to emphasize some really cool things about the mathematical expression for a particle’s magnetic field: This is really a single particle form of the Biot-Savart law. […]
Read More Matter & Interactions II, Week 7I’m writing this a whole week late due, in part, to having been away at an AAPT meeting and having to plan and execute a large regional meeting of amateur astronomers. This week was all about the concept of electric potential and how it relates to electric field. I love telling students that this topic […]
Read More Matter & Interactions II, Week 6This week was all about calculating electric fields for continuous charge distributions. This is usually students’ first exposure to what they think of as “calculus-based” physics because they are explicitly setting up and doing integrals. There’s lots going on behind the scenes though. In calculus class, students are used to manipulating functions by taking their […]
Read More Matter & Interactions II, Week 5This week was entirely flipped in that class time was devoted to letting students do whatever they needed to do to practice with the material in chapters 13 and 14. Until now, no one has touched the WebAssign problem sets or much programming. In an administrative environment where “teaching” is defined as lecturing from a […]
Read More Matter & Interactions II, Week 4