In introductory physics labs, a challenge arises when students are asked to measure a well-known quantity, such as the free fall acceleration, g. Students often don't perform a proper error analysis if they already know the correct answer, and their result is “close enough.” Masking, or disguising the correct answer, as is often done in nuclear and particle physics research, encourages students to be more careful. In this paper, we introduce a new unit of measurement; in these units, students don't know what the value of g should be, leading to a more engaging and authentic scientific experience. Additionally, we instituted a mock “conference” in which students settled on a consensus value of g in this new system of units. When students quantitatively compare their measurements of an unknown quantity, it motivates them to perform a detailed error analysis. Student feedback on this reformed lab was largely positive.
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At the end of the Conference day, several students asked if we would continue to use the aub sticks in upcoming labs and specifically asked if they could be updated on the results of future labs to see how the accepted value would improve. The students showed a genuine interest in what they did beyond just getting a result and moving on to the next experiment: They were interested in seeing how this new unit would develop.
© 2024 Author(s). Published under an exclusive license by American Association of Physics Teachers.
2024
Author(s)
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