Learn more about why we see rainbows! Drag the hand to change the wavelength of the light, and see how that affects the angle that the light bends when going in and out of the prism. The tools let you look at angles with a virtual protracter.

I haven't yet seen this on a PC, so I'm not sure how the colors look on that platform. I also plan to add more color variations to the light beams when I find some time.