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!
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…