Geek Celebrates Hanukkah With Science: Day Six

It’s the most wonderful time of the year – for science! If you haven’t been following along with my family this Hanukkah, you’ve got some catching up to do. We’ve already launched a rocket, sank a few boats, transformed math into a form of dessert, poured some stripes in a jar, and danced with the raisins.

Tonight, huddled in a dark room with flashlights at the ready. We’re not afraid of the dark, we just wanted to unweave a rainbow. Or at least project one onto a wall.

This experiment has so much potential for discussion. After we finished playing with refraction and the visible spectrum, we talked about differences between human color vision and animal color vision, color blindness, and ultimately about light, the universe, and everything.

The instructions for this experiment are simple (materials are in bold):

  • Fill a tall drinking glass or glass bowl with water.
  • Darken the room as completely as you can.
  • Shine a flashlight through the water onto a white wall.
  • Voila! Roy G. Biv!

Note: There are many alternate ways to perform this experiment. Try them all! And let me know if yours show up better on video than ours did. *mutters* I swear, it was gorgeous in person, no matter how wimpy it appeared on camera…

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