6A44.45: Laser Waterfall
Description: This demonstration shows total internal reflection through a stream of water.
- Jack stand
- Laser waterfall container
- Powdered milk
- (Optional) Pyrex beaker
- (Optional) Red food coloring
- With the cork in, fill the container up with water.
- Mix in a small amount of powdered milk.
- Place the container on an extended jack stand. Position it so it aims at the sink.
- Aim the laser straight through the container at the cork.
- (Optional) Fill a pyrex beaker full of water, add a drop of red food coloring, and place it in the sink without students seeing.
- Turn on the laser. Double check to make sure it's lined up on the cork.
- Turn off the lights.
- Pull the cork plug out.
- Note that the laser beam travels in the stream of water. This is due to the laser light exhibiting total internal reflection.
- Turn of the laser.
- (Optional) Pull up the beaker with red food coloring. You can say you traped all the laser light