Geek Celebrates Hanukkah With Science: Day Eight

It’s been another wonderful science-driven holiday season! We’ve experimented with balloons that blast-off, nearly unsinkable dinghies, delicious math candies, stackable liquids, desiccated dancers, split light, and put a minature Jaques Cousteau in a bottle. Tonight we’re going to give Hanukkah a fine send-off with another trick of the light.

 

I got the idea for this experiment, not from the internet or a science book, but from a simple game I developed to teach my five year-old about angles. We call it the Acute Obtuse game, and all it takes to play is a ball and a wall. But balls aren’t the only bounce-able toys. It’s easy to turn wall-ball into flashlight geometry.

 

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

  • Draw a target on a paper plate, and tape it to a wall or ceiling.
  • Using modeling clay, stand a discarded CD upright on a paper plate.
  • Turn out the lights in the room.
  • Shine a flashlight on the CD and try to angle it so the reflected light hits the target.
  • For more fun, use a laser pointer and multiple CDs to hit targets hidden behind obstacles!
Liked it? Take a second to support GeekMom and GeekDad on Patreon!

Share
Published by

Recent Posts

Perfect for Spring, Marimekko Brings Bold Color and Design to Stationery

Bring springtime and color into your home with Marimekko stationery items.

March 9, 2026

The Winter Goddess by Megan Barnard

The fight between winter and the onset of spring is something we know well in…

February 18, 2026

If you are looking for a way to escape this never ending January, a trip…

January 30, 2026

‘Mouse Guard: Dawn of the Black Axe’: Interviewing David Petersen on the Black Axe’s Origin Story

Out today is the newest Mouse Guard book, 'Mouse Guard: Dawn of the Black Axe'—and…

January 20, 2026

The New Rubik’s x Tetris Cube Is a Fun Mashup of ’80s Toys

If you like some extra squares in your cubes, check out the new Rubik's x…

December 22, 2025

Skye Sweetnam, Sumo Cyco, and the Power of Community

Like many others, I jumped directly into my Apple Music Replay this year filled with…

December 17, 2025