|MadSci Network: Physics|
Hi Aaron-- You didn't give me one key piece of info...however, I shouldn't need it. I'm guessing by the sound of the situation that the end of the tube where the water level is lower is open, and the other end is closed. Even if the tube is not completely open on that end, this will happen. The reason for this is that the air pressure in the room will push the water down a bit if the tube is open. This is the idea behind the barometer, and if the tube had markings on it, you could use it to measure the air pressure in the room, although mercury would be a better liquid to use in that case. Hope this helps!
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