66 Today some conceptual students did their first “practicum.” They timed how long it took the slow-acceleration disk to roll one meter down its ramp. Then they had to determine how fast it had been going when it passed the 1-m mark. While they timed it, I took video. While they debated how to find the answer, I did video analysis. They told me the answer was 0.16 m/s and then Tracker told me the answer was 0.164 m/s. So I told them that they got it right. They were a little stunned, I think, and I hope they were also proud of themselves for doing it. Next step: more complicated questions.