# Day 84: Physics Circuit Training

Thursday, Feb 1

Physics: Continuing waves! We did the bell jar demo a couple times so they could hear the difference, as well as using the music box for forced vibrations. That was a real jaw dropped. I love it so much. I mostly have them excited about waves, and tomorrow we’ll talk about the Tacoma Narrows Bridge which is p much the best video of the entire year as far as I’m concerned.

Honors Physics: Last day of studying before tomorrow’s exam.

AP Physics: Today we analyzed the data, and it turned out the data was largely garbage. SURPRISE SURPRISE. So, we took more careful data and looked for specific patterns. I don’t consider any of it wasted time, because now they can quickly and easily take the more careful data. There was a lot of unclear language being thrown around like “more resistors adds resistance!” and “current across a resistor” and “the voltage is always the same” and “resistor uses up current” and all the things they always say at the beginning that I have to BEAT OUT OF THEM WITH A HAMMER. Thus, today begins the forging of their correct understanding of circuits.

So we started breaking down individual relationships of current/voltage/Req in series/parallel circuits. They really, really, REALLY just wanted me to tell them things that were true. I made them look at the data to find patterns, but there weren’t reliable patterns. This is my surprised face. So! More building and measuring! They’re surprisingly surly about doing lab activities in our actual dedicated lab time. First they didn’t correctly measure the voltage across each resistor in series, and now they’re looking to find an overall pattern in how Req is related to individual Rs in parallel. I’m desperately trying to get them to see that the Req in parallel is always lower than the lowest resistance. That’s the discovery I was after, and eventually they figured it out, so then we finished our model of a circuit, went over some basic examples, and very briefly touched on what capacitors are and do in a circuit.

The second class went through in 10 minutes what took 50 for the first class, so I ended up with a lot of extra time for them to do practice problems and write their own problems and do a couple released AP B problems. They’re really, really enjoying it in my second class, and teaching the first class is like pulling teeth. I need to think on this and figure out how better to serve the first class.