One of the “bobs” about to be released.

The data collection station.

Ken Kessenich at Pius XI High School in Milwaukee, WI found a great way to get his students more involved in his pendulum experiments. Using the laser gate feature of the new Vernier Photogate, Ken used an inexpensive laser to create a gate that was 4 meters wide and used 7.7 meter long pendulums with MUCH bigger bobs than usual: students!

Pendulum lengths were kept constant by belays from the Phys. Ed department, and changing the mass was as easy as finding new volunteers. Ken was able to get 50 out of his school’s 120 physics students to arrive early to participate. Students were released from different heights in the gym bleachers to allow release angles between 26 and 41 degrees, allowing them to change two of the three variables in the experiment. Based on the popularity of this exercise, the track coach invited him to use a two-gate setup to help runners determine their maximum velocity during a sprint!