I wanted to do a resistance paradigm lab to start the circuits unit in AP Physics 2. I found a Nature of Resistance series of activities from ￼￼the CLASSE Institute for Physics Teachers. The activities seemed well designed and emphasized the connections between macroscopic observations and atomic interactions. Today, after an introduction with an incandescent light bulb and the standard Modeling Instruction paradigm lab discussion, students focused on graphically and mathematically modeling the relationship between resistance and either length or cross-sectional area of the Play-Doh resistor. The accuracy of the data wasn’t fantastic, but they had a lot of fun and saw the relationships among the variables.
2 thoughts on “Day 61: Resistance Paradigm Lab with Play-Doh!”
I’m curious how much the volume changes when you stretch playdoh. If it doesn’t change, then this connects quite well to R=\rho L/A. If it does change, then the \rho changes too.
Play-Doh does stretch some. I think that effect was minimized particularly well when students modeled the relationship between resistance and length because they packed the Play-Doh in the PVC mold. When investigating resistance vs. area, it may have played a more significant factor which may explain why those results were not as close to the expected relationship.