Yep, I missed again last night. But, I have another good reason. I was invited to speak to a group of students at UWO. In the College of Education, there is a program called ACT (Alternative Careers in Teaching) for people looking to get into teaching, and get on a fast track to student teaching and licensing. I was one of five panelists talking about use of technology in the classroom. I was asked to spend about 30 minutes talking about the use of Logger Pro and how I use our high-speed camera. Petty easy for me! It was an interesting evening and I learned about a few new pieces of technology that I did not know about.
We checked the Buggy Bash. As I mentioned, I like the intersection collision so here are a few clips for you viewing pleasure:
The really good:
and the ugly:
We did a practice problem involving the thin lens equation. We set up an optics bench, located an image and used the object and images distances to determine the focal length. The second type was to use the known focal length to predict where an image would be located with a new object distance. This one is fun because you have the students predict it and then set the screen, then switch on the light and look for the perfect image. It sometimes surprises them when it really is perfectly in focus. We then talked about how the ray diagram and our linguistic model allows us to predict some information about the size of the image, but the thin lens equation does not. Enter the need for another (equation) way to determine that… the similar triangles. Back to practicing, given this object distance and focal length lens, predict the size of the image. So now we have a two set problem!