Science experiment: Cartesian Diver

Here's an experiment that will keep the children busy while they learn a little science. The Cartesian Diver experiment teaches children about buoyancy.

Ingredients

• 1 glass medicine eyedropper
• 2-liter bottle with cap
• Water

Instructions

STEP 1: Fill the 2-liter bottle with water.

STEP 2: Squeeze a small amount of water into the eyedropper.

STEP 3: Place the eyedropper into the 2-liter bottle and screw the cap onto the bottle.

STEP 4: Squeeze the sides of your bottle and watch as the eyedropper sinks to the bottom.

Explanation

When you push on the sides of the bottle, the eyedropper becomes less buoyant and sinks.

Jason Lindsey is a science outreach educator at Discovery Playhouse. Check out his science blog "Hooked On Science" at jasonthescienceguysblog.blogspot.com/ for Web casts and tools you can use at home to get hooked on science. You can reach him at 573-334-0416; jlindsey@discoveryplayhouse.org or PO Box 1251 Cape Girardeau, MO 63702.