How to improve the Collisions Lab

Presenter: Kevin Vasquez

Presenter Status: Undergraduate student

Academic Year: 22-23

Semester: Spring

Faculty Mentor: Hongtao Shi

Department: Physics & Astronomy

Abstract:
When an elastic collision takes place, there should be no loss of total kinetic energy and total momentum in principle. When students take the introductory mechanics lab in Physics 116 and 209A, however, we often notice that results vary greatly from one student group to another even if they are all following the same lab procedure to work on the same head-on elastic collision experiment. The loss of total kinetic energy is often as high as 30%. Our project is to try to understand what has caused such a big discrepancy between the theory and the experimental results. We have discovered that factors such as whether or not the track on which the collision takes place is clamped to the table, the friction between the moving carts and the track, the distance between the photogates are all responsible for such a big discrepancy. We will use this work to revise the lab write up to better support the students.