Day 137: Universal Gravitation & Glacier Video

After no classes yesterday due to state testing, we got back in the swing of things today.

AP Physics: Universal Gravitation

Today continued quick and dirty coverage of some topics on the AP exam that we haven’t really addressed yet. Today, I asked students whether uniform circular motion or free fall is a better description of the Moon’s motion, and students went very quickly to wanting to find the acceleration, so I gave them the Moon’s period and orbital radius, and got out of the way. This served as a nice refresher on circular motion. Once students got a tiny acceleration, we reasoned that a 1/r2 relationship might make sense for gravity and checked that against gravity at Earth’s surface and get to the Law of Universal Gravitation.  Then, since most of my students saw Coulomb’s Law in chemistry, we used the parallels with gravity to make sense of that formula.

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Earth Science: Glacier Video

With conferences tonight, I went ahead and showed the video in the curriculum for today. The video was about the data sources glaciers can provide, which got me thinking about how to have students explore those data sources in the lab. For glacier movement, I’m wondering of something like gak could be used to simulate a glacier, maybe with food coloring drops or toothpick flags to track specific points. For the ice cores, I was thinking it would be really cool to find some scale photos of actual ice cores, especially if I could find a way to have students compare the core data to weather data for that year. Of course I thought of all this while watching the video, rather than last night while I stared at the curriculum materials. Oh well.

Day 136: Electrostatics & Permeability

AP Physics: Electrostatics

I missed class for a field trip today, but the rest of this week is all about squeezing in superficial coverage of the last few topics. Today, students worked some problems I wrote to refresh their memory on some electrostatics from chemistry, then help them reason their way to what they need for physics. There are no classes tomorrow, so I’ll find out Thursday how it went.

Earth Science: Permeability

Students whiteboarded yesterday’s lab results, then we did a quick demo on permeability. Then students used what they’ve learned to design an aquifer.

Day 135: Closed Pipe Waves & Porosity

AP Physics: Closed Pipe Waves

I started class by showing students a few examples of sound waves in open pipes to establish that standing sound waves follow the same rules we saw last week for a standing wave on a string fixed at both ends. Then, I had students use our speed of sound materials to find the pattern for sound waves in a closed pipe. To keep the follow-up discussion short, I went back to standing at the front of the room and asking students to share their general results. In one class, students spontaneously started answering my questions by pointing out a lab partner who’d said something interesting and asking them to share, which lead to some students who don’t always speak up in whole-class settings getting their voices heard, which was pretty cool.

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Earth Science: Porosity

Students designed their own experiments to compare the porosity of sand, gravel, and Play-Doh. Students needed a little more scaffolding on how to measure the amount of water absorbed, but they ended up with nice results overall. Tomorrow, we’ll spend some time connecting these results back to the structure of aquifers.

aquifer

Day 134: Board Meeting & Artesian Wells

AP Physics: Board Meeting

Students whiteboarded the results of yesterday’s lab. Several students had already seen λ=c/f in AP Chemistry, and I was pleased to hear them discussing how their results fit with that formula.

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Earth Science: Artesian Wells

Students simulated an artesian well to find how the change in elevation affects the flow rate. I wish I’d spent more time on the pre-lab discussion to help set up what students should measure and why. I really liked the connections to energy it was possible to make; a few of the students I had last tri sketched bar charts and were able to generate some very nice explanations for why the big elevation change produced a high flow rate.

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Day 133: Standing Waves & Glaciers

AP Physics: Standing Waves

Today started the standing waves unit. I gave a quick overview of standing waves using a simple sim in Desmos, then we got out the wave generator to collect data for a relationship between wavelength and frequency. To save time, we collected data as a class, but students felt very little connection to the results. Last year, I had students use a Direct Measurement Video to get the same kind of data, then used the wave generator to test some ideas, and I think I’d like to go back to that approach next year.

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Earth Science: Glaciers

Students used the textbook to dig into how glacial features are formed. While I wish I’d been able to come up with something more tangible, there were some good conversations about how to effectively use the textbook.

Day 132: Problems & Glaciers

AP Physics: Problems

Students worked on some oscillating particle problems. Students had some really good discussion about a cart on an angled ramp oscillating on a spring; a lot of groups really dug into what should happen when the angle of the ramp changes. At the end of the hour, we tested their predictions. I wasn’t paying much attention to when I started data collection, but still got a set of graphs my 2nd hour considered applause-worthy.

 

 

Earth Science: Glaciers

I gave students a brief overview of some glacial features, then had them use some sand in the stream tables to make a recreational area with a variety of glacial features. Students liked the activity, but they did not connect the vocabulary to how the features form or how they are related. I think I’d prefer to do this at the end of a glacier unit, where students would have the background to tie the features they are using together. At this point in the unit, I’d rather focus on how these features form to give some basis for naming them.

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Day 131: Pendulums & Springs & Dam Removal

AP Physics: Pendulums & Springs

Students wrapped up their labs on what affects the period of  springs and pendulums, then whiteboarded the results. I could tell I was rushing the lab more than I have in the past and I ended up taking over a lot of the post-lab discussion and got a bit hand-wavy. As I rush through the last few topics, I haven’t been doing as much with uncertainty, and this is a lab where it would have really helped. I also skipped having students predict the period of a 5 m long pendulum, which made it much tougher to settle on which relationship works best for the length of a pendulum. Going into waves, I need to think about how I will balance the need to keep moving with giving students time to truly engage with the content.

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Earth Science: Dam Removal

Students continued work on their dam removal project. Today, they looked at a gradual release, which we modeled by removing one lay of foam at a time. I was very pleased at some of the detailed observations students made and how engaged they were in trying to think about why their observations happened. I’d love to re-work this unit to give students a better grasp of sediment transport in rivers before looking at dams specifically to give them more tools for thinking about the project.

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Day 130: Plickers & Dam Removal

AP Physics: Plickers & Quiz

We continued our routine of Plickers to practice some multiple choice questions, followed by a quiz on this week’s new material. I’m continuing to have students pick an answer individually, then discuss and vote again. There were a couple where students struggled to identify useful representations and, once I gave a nudge, they quickly got to the correct answer. I’m thinking about working in a step where students identify applicable models before they pick an answer to help with that.

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Earth Science: Dam Removal

Students used stream tables and a foam model of part of the Salmon River to get some background knowledge for their engineering project. They conducted some observational experiments on sediment transport and deposition, first in a natural, unblocked river, next in a river with a dam, and finally when the dam is removed with a “blow-and-go” approach, where the entire dam structure is removed at once.

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Day 129: Period & River Features

AP Physics: Period

Half the class did experiments to model the period of a pendulum, while the other half did experiments to model the period of a spring. We have three types of springs, and their spring constants are different enough that you can’t test all three with the same mass. Next year, I might have students start by using one spring to test how amplitude and mass affect period, then check their model with a second spring.

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Earth Science: River Features

Today, the curriculum called for notes on typical river features, followed by students looking for those features in topographic maps to classify rivers as young or old. Before we did any notes, I had students sort the rivers based on their own categories. They based their categories on things like width or windiness that resulted to very similar sorts to young and old and lead nicely into the vocabulary. When students went back to their groups to sort the rivers by age, I noticed students got less accurate, largely because they interpreted small curves as meanders, making rivers seem older.

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Day 128: SHM Energy & Floods

My classes had a sub while I chaperoned a field trip today, so no photos.

AP Physics: SHM Energy

Students worked on some problems on the role of energy in simple harmonic motion. While there aren’t any circular motion problems today, I’ve been liking the connections we’ve made to circular motion and I’m spending the bus ride thinking about if and how I want to connect today’s work to circular motion.

Earth Science: Floods

Students watched a video and answered some questions on flooding.