Cartesian Diver

This project helps you to understand how a submarine works. A submarine filled with water to make it sink and the water is released to make it float.

Materials Required:

• An eyedropper or bottle dropper
• a plastic bottle with air tight lid
• A cup of water

Procedure:

Fill the bottle with 3/4th water and drop the bottle dropper or the eyedropper into the bottle and close the lid air tight. The eyedropper's tube should point towards the bottom of the bottle. If this doent happen stick a gum to the end of the eyedropper where the hole is. Do not close the hole. That is it. When you press the bottle, you will notice the eyedropper sinking. When the bottle is released, the eyedropper floats.

Inference:

When the bottle is squeezed, the water enters the eye dropper through the hole at the bottom. This water forces the air inside the eyedropper to compress thereby making the eyedropper heavier than the water. Hence it sinks. When the bottle is released, the compressed air inside the eyedropper forces the water out and the eyedropper become light and moves to the surface to float.