May 06, 2010
Reflections on reflection.
Today in "Light and Atoms" we looked at the ray model of light. The goal was to be able to understand how the rays from a light source (or object) behave in order to use ray diagrams for curved mirrors and eventually lenses. We spent quite a bit of time on our discussion and had to rush through the activity at the end.
I handed out plane mirrors, corkboard and pushpins for a law of reflection activity. Many of the students had to leave before they completely finished the activity, but those who stayed really liked it. That's definitely a keeper activity.
The lab we did today was a lab exploring the formation of images by converging mirrors. I had the students use the lab writeup in their textbook. I got the sense that while the class completed the lab all right, I would be surprised if most of the students actually understand the reflection off concave mirrors at the level the lab was written at. One of the TAs even commented that there are some labs which do not work well to facilitate learning and that this was one of them.
I don't have any answers as to how to better teach reflection off of curved mirrors. I need to refer to some of my favorite sources for inspiration.