In the previous post, I discussed the rubric for an AP Physics question that required graphing data. A number of folks requested that I show and discuss the most common mistakes on this type of question. I should emphasize that while I am speaking in the context of grading the AP Physics exam, the graphing issues here are germane to experimental physics at any level. Even in the most basic conceptual physics course, even in our professional level Research Physics course, appropriate graphing skills should be developed.
Don't let your students' graphs look like these. You may laugh at some -- just the mere fact that you're reading this blog implies that your students would be less likely to make most of these mistakes. But understand that every one of these mistakes is made FREQUENTLY on the AP exam.
BAD GRAPH #1: Non-linear axes