In this clip, the students are gathered around in a whiteboard circle. The discussion is regarding the energy of a two-mass and pulley system. The students discuss whether or not the pulley’s energy should be included. The students also discuss the affect that the rope itself would have on the energy. The professor leads the class to the idea that in this problem the pulley’s energy doesn’t contribute, and also reminds them that the rope doesn’t stretch.
This clip takes place during week 6 (Becoming Quantitative with Energy). The problem that the students are working on is problem #2 from the “Energy Problems for Practice” worksheet.