Wednesday, 30 October 2013
I introduced refraction today. My opening: “John Stewart / Green Lantern can become invisible. How?”. I offered them two scientifically-plausible scenarios (here and here). We demo’d the first in class:
The kids dismissed baby oil because they understand Green Lantern is visible because light reflects off him. We settled on the second scientifically-plausible invisibility mechanism as the best for him.
After the baby oil / beaker demo, we looked at refraction and then Snell’s Law. I took the opportunity to explain that Willebrord Snel van Royen wasn’t the first to describe refraction. That honor belongs to ibn Sahl, a Persian mathematician in 984 Baghdad.
What was the warmup 7th period?