139 This was Tuesday, 4/16. The AP class was determining the relationship between the magnetic field strength and distance from a long current-carrying wire. Almost all of my photos turned out blurry. I am not sure what I had messed up in my phone’s camera settings.



131 It’s RC circuits and capacitor discharge time in AP Physics! (Post originally meant for April 4th)


IMG_20130307_102401114 The AP class is making capacitors out of aluminum foil placed between the pages of books. We are hoping that the capacitance is proportional to area, inversely proportional to the distance between the plates, and we also hope to determine the dielectric constant of textbook paper.

Free Fall

102 When we investigate free fall, we drop picket fences, and we also fling them upward using rubber bands. This does not work every time, but it is quick enough to get five good trials with usable slopes. We compare the slopes of these graphs to the slopes of graphs made with the dropped picket fences.




96 The data are starting to come in from the video analysis. Not enough yet to tell what the graph will look like. I decided to pull all the data together in a Google Doc.



IMG_20130130_10132591 Wednesday’s experiment involves determining the moment of inertia of a disk. It will also be placed vertically to be spun around a diameter.

Moment of Inertia

IMG_20130129_09345690 We finally got in our moment of inertia equipment, paid for by the PTO’s Mini-Grant program. I actually have enough equipment for every group! Tuesday was the day for moment of inertia of a point particle.

N2 Lab


75 It is time for the conceptual classes to learn about the relationship between acceleration, force, and mass. We’re doing modified Atwood’s, varying total system mass first. As you can see, we are not a single-vendor school. I don’t even know where those little hanging mass sets come from, but I like them!



20130104-130620.jpg74 My 5th period class had some great results from their practicum with the coffee filters. One group got a time only 0.04 seconds off their “given” time, and another group (shown above) got only 0.01 second off their “given” time! Wow!


Coffee Filters

20130102-131014.jpg72 Starting off the new year with a lab. This is a coffee filter drop lab, in which students model the motion of a coffee filter from data they take in class, then they predict how high they would have to drop it from in order for the filter to take a given amount of time to hit the floor. The tricky bit is the room is less than 3 meters tall, and invariably they calculate a height greater than 3 meters (I’m sneaky about how I pick the “given” times). We have to go out to one of the stairwells to test the prediction. A good model results in a drop time within 0.1 s of the given time.