This week the AP Physics 2 class is taking a break from our modern physics unit to prepare for our field trip to Fermilab to participate in a Particle Physics Masterclass. Today’s activity, Rolling with Rutherford, focused on the important role of indirect measurements in particle physics. Students roll a sphere at a line of other spheres that are obscured. Based on the ratio of collisions to rolls, students can calculate the radius of the target sphere! In previous years, we derived the necessary equation together. This year, I left it to each group. Most groups needed me to ask what effect, if any, the width of the incident sphere has on the calculation, but with that guiding question, they were able to derive the necessary equation.
The results were excellent: 1.3 cm calculated vs. 1.27 cm actual!