Water Bottle Rocket

First you take a 2 liter pop bottle, then you take a cork (Value Home center) and put a basketball pin right through the middle of the cork. make sure the cork is big enough so that not a drop of water can leak out. Next you connect the pin to the airpump, and fillthe bottle 2/3 with water and stick the cork allthe way until it reaches the bottom of the neck of the bottle. you can add fins to stand it up or have someone who is willing to get wet hold it. Turn the bottle upside down and begin to pump and after 10 or more pumps the bottle should launch. Try different size bottles with different corks. ( the smaller bottles go higher){{{

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