An experiment on water pressure and height
Answers
The water in the bottle is squeezed by the height of water on top of it. The same happens with the water in the straw. The air inside a balloon is under pressure as it is squeezed by the rubber. When you place the inflated balloon on top of the bottle, the air pressure on top of the bottle becomes higher.
Explanation:
Air Pressure and Straws
For this air pressure experiment, students should fill a 2-liter plastic bottle with water halfway. Place a large straw in the water so that it extends out the top of the bottle. Cover the opening of the bottle around the straw with clay so that no air can go in or out except through the straw. When students blow in the straw, it will raise the air pressure in the bottle. That air pressure will push down on the water, and with no other place to go, the water will escape through the straw.
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