In the Modeling Instruction materials for Physics: E&M, there are videos provided that can be analyzed to develop quantitative relationships between electrostatic force, separation distance, and charge quantity. However, this process is rather complex and requires using distance as a proxy for force. While the inverse-square relationship comes out (though even that can be difficult to determine if students aren’t very careful about the video analysis), it does not allow for a determination of the Coulomb constant, since the charge of the objects in the video is not known.
To try to remove some of the difficulties while still using the data analysis to develop model for electrostatic force interactions, I developed a simulation that allows a more direct “measurement” of charge, distance, and force.
This simulation is great to use in combination with my data analysis tool to analyze the relationship between distance, charge, and forces.