# Semester 2 – Day 4

Given how poorly my students did on the final, I’m worried that I’m going back to an old habit. namely I’m trying to do too much of the intellectual “heavy lifting” for them. Mentors have observed me and given me feedback, to the effect, that I sometimes over-instruct or talk too much instead of letting the students do. I am worried that this habit is rearing its ugly head again.

Today we did the weight mass lab. it’s a very straightforward lab in which masses are hung from a spring scale. The mass is given in kilograms, and the force measured on the spring scale is, of course, in Newtons.

The weight, which is read off the spring scale is plotted versus the mass in kilograms. The slope of this plot is the gravitational strength of Earth, that is 9.81 N/kg.

The spring scale reads force in newtons, and it also reads mass in grams. Furthermore the masses themselves are given in grams.

I’m worried that I spent too much time explaining the proper units to use on the Y and the X axis. Should I have simply told them what units I wanted them to use and let them fumble around till they got it right? Or are such mistakes basically exercises in futility? I don’t have a good answer. I think, though, in the next lab I will give them much less direction