Wednesday, 2 July 2014
Today we demonstrated conservation of energy using a pendulum and photogates. I based my lab almost 100% on one I found online. Here’re my lab and the one I found online. I heard a few aha moments from the kids (like when they connected the total energy here equals the total energy there). While there were a few awkward parts about the data collection I didn’t like and this lab was far too prescripted for my taste, it went well overall. I think my kids spent about an hour on it.
We find Desmos to be the easiest way to graph data points and fit trendlines. I absolutely love using sliders to make a function fit a set of data. So intuitive! The technology takes the tedium out of precise plotting of points but leaves a manual line fit (it’s less magical when they have to manipulate slope and y-intercept of a line). In case you’re curious, we plotted GPE vs KE to see if they were virtually identical.
Next year, I’ll ask the kids to show that GPEi = KEf before doing anything. I’ll also let them come up with ways to set up the data collection.
That said, I do love me some ballistic pendulum action AND I spotted some in a colleague’s room earlier this week. I may just ditch this lab altogether in favor of the ballistic pendulum.