Today is the first of three days of semester finals. AP Physics 2 students spent our final exam period exploring each others’ capstones and providing feedback. Since the capstones are published online, students are able to incorporate their peer feedback even though they have already “submitted” their capstones by submitting links via a Canvas assignment. Some students also took advantage of the time to review for their other final exams.
Today is the school’s official “review” day in preparation for finals which start tomorrow. Since the capstone projects are the final, we spent today wrapping up loose ends like surveys for the district’s Digital Learning Initiative (1:1 Chromebook pilot) and making sure everyone’s capstones were published. One student modeled a magnet falling through a copper pipe. We had some leftover liquid nitrogen and so we explored the affect of the temperature of the copper pipe on the rate at which the magnet falls. The colder pipe definitely resulted in a slower descent!
We had fun freezing various parts of students’ lunches as well. All was fun until the dewar accidentally got bumped off the table and broke. Loud bang, big mess, expensive replacement 🙁
Today is the last day for students to work on their capstones since they are due tonight. I’ll share some of the published capstones later. The in-progress capstone that I’m featuring today is a student who is performing a post mortem analysis on Physics Club’s recent high-altitude balloon launch. We’ve launched several high-altitude balloons in the past and our most recent launch was a couple of weeks ago. The payload encountered very high winds during flight and it appears that the tracking device became separated from the rest of the balloon and payload around 80,000 feet. As a result, we only recovered the tracking device and not the rest of the payload with our parachute, sensors, data, and video cameras. We are hopeful that someone will find the payload and give us a call as our name and phone number are on it. This capstone is modeling where the payload may have landed based on when the balloon burst. Lots of area to search!
Today I’m featuring a student whose capstone is to investigate at what velocity a Nerf dart loses its stability in flight. Part of his investigation is to determine the drag force on the Nerf dart at various velocities. Huge thanks to my colleague for preparing the wind tunnel, which is used in the R&D classes, for this student!
Today, I’m featuring a fantastic capstone. This student has used an Arduino to create an EMG sensor. He’s attempting to characterize the signal such that he can determine the amount of weight being lifted based on the signal from the EMG. Really cool biophysics application!
Today, I’m featuring one student who is calculating how many balloons would be required to lift a house as done in the movie Up!. We had some leftover helium from our recent high-altitutude balloon. I like his approach which starts with filling 13 balloons with helium and connecting them to a force sensor.
AP Physics 2 students continued to work on their capstones. Today, I’ll feature one student’s capstone which is essentially a paradigm lab for an electric motor. We won’t study electromagnetism or electromagnetic induction until next semester. He saw a video showing how to build an eclectic motor and wanted to determine what affected the rotation of the armature. Maybe we’ll use his capstone when we investigate electric motors next semester. I like how he is using a photogate to measure the rotation of the armature.
Today, AP Physics 2 students had their first day of in-class work on their capstones. They must submit their initial idea by the end of the day tomorrow. I’ve already heard so many fantastic ideas. This year’s capstones should be amazing and really varied. Usually I have to sign out the laptop cart of iPads all week for student research and work. This year, most can use their Chromebooks. Those students doing video analysis need a laptop.
I was off campus today at the annual AP Science Symposium while my AP Physics 2 student finished their circuits exam. I am fortunate that a nearby high school hosts an annual AP Science Symposium. This year, nearly 30 AP Physics teachers attended. It is fantastic to spend the day asking questions, listening, and sharing with peers from other high schools. I was pleasantly surprised at how interested and receptive the other AP physics teachers were to Modeling Instruction (historically the philosophy of these teachers hasn’t aligned much with Modeling Instruction). I think the new AP Physics 1/2 courses and their emphasis on deep conceptual understanding has created this opportunity. My colleague shared his recent experience administering a goalless lab practicum, which is an idea I have to try!
Today, we did some peer instruction of conceptual circuits questions as a review before the multiple choice portion of the exam. Due to short periods tomorrow, I moved the multiple choice portion of the circuits exam to today. The question that generated the best discussion was this one:
Listening to the justifications, I realized that the values specified in the question have the potential to leave students with a misunderstanding. Some groups discussed how after the switch is flipped the two capacitors have to end up with the same charge. They didn’t appreciate that, while their answer was correct, the two capacitors only have the same charge because they have the same capacitance. The correct justification is that the two capacitors must have the same potential difference after the switch is flipped and current has stopped flowing. This realization is a result of the peer instruction discussions that I listen to. If I simply looked at answers, I wouldn’t have realized that students didn’t correctly understand the answer to this question. I’ll change this question for next time!