You need:
THE WATER FOUNTAIN
Make a fountain in your room.
two bottles, one full of water and the other empty a cork stopper a long plastic drinking straw a thin drill bit plasticine putty
How the experiment is performed: 1. Drill a hole for the straw through the cork lengthwise. 2. Plug the empty bottle with the cork and insert the straw. 3. Use the putty to seal any gap that might exist between the straw and the cork. 4. Suck some air from the bottle and quickly seal the straw with your finger. 5. Turn the bottle upside down and place it on top of the bottle with water, inserting the end of the straw into the water. What will happen: Water will come out of the straw like a small fountain. Why? The pressure exerted by the outside air on the water in the lower bottle is higher than that of the air in the upper bottle, causing a difference in pressures which forces up the water.
Additional idea: Look at the picture on the right. Insert two bent straws through the cork as shown, one long enough to dip down into the water. Now blow into the other straw. As you blow through the shorter straw, water will flow out of the bottle through the other one.
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