Physics: Big Pendulum

Before discussing the results of yesterday’s pendulum lab, we went to the main entrance of the school where we could hang a string from the second floor down to the first to make a 5 m long pendulum. Students used their mathematical models to predict what the period should be. Most groups used a linear fit for their data, and ended up predicting a period that was too big as a result. The really long pendulum provided a reason to refine their models by collecting more data and trying some linearization.

Chemistry: Conservation of Mass

Students reacted calcium chloride, baking soda, and bromthymol blue in a Ziploc bag, making sure to take the mass of everything at various stages. This tri, I gave each group a beaker to place their bag in when using the balance, rather than having them set the bag directly on the balance pan, and the results were much better; students were able to use their results to articulate the law of conservation of mass very nicely.