Refraction

Sam taught some of the lessons on refraction since he knows a lot more about it than I do! He may have gotten a little carried away when discussing how to calculate angles of refraction, but even if we didn't get it all, we learned a lot! :)

Sam had the children roll toy cars (photons) in a straight line on the hard floor and see what happened when they reached a different material (the carpet). It was a great demonstration of how light changes speed (and often, direction) as it passes through different media.

Refraction at work: you can see the house outside refracted upside-down in the curved water glass!

We saw how even a curved water-drop can act like a lens, to refract light and magnify what is beneath it.

We saw how chromatic aberration can occur as light refracts and separates just slightly into its different wavelengths.

A laser's light being refracted through water

These lenses were great for experimenting with refraction, and how different shapes cause light to refract at different angles.

Sebastian even found an incident angle that made nearly all of the light refract and reflect inside the glass, back out of the other end of the lens! I think something similar to this is occurring inside a fiberoptic cable to keep the light inside the cable as it goes around curves and corners.

If you don't have lenses and lasers to use, you can download this angle of refraction simulator to experiment with how light bends through different objects. I think there are mathematical ways to figure this out for yourself, but I don't know them! It was interesting to see how different materials affected the refraction of the light.

Here's a video that discusses these concepts. It gets a bit technical in parts, but we liked the animations (and the narrator has a great accent!) :)