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Q & A: holy canoes

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Most recent answer: 10/22/2007
Q:
If I was on a canoe and water from rain had settled at the bottom of the canoe, what would happen If I drilled a hole at the very bottom of the canoe. Would water pour in, or is the air pressure enough to let the water seep out back into the lake?
- Anonymous
Springfield,VA USA
A:
Neat question.

Generally you expect things to fall down, lowering their energy. Let's figure out whether the water would drain in or out to lower the energy here. In other words which way ends up with more heavy stuff farther down?
If the water drained out of the canoe, the canoe would float a little higher. If it drained in the canoe would float lower. The reason a canoe usually doesn't sink is that pushing it down pushes some water up, replacing it with the air in the canoe. Unfortunately, with a hole in the bottom, that will be water, not air, in the bottom of the canoe. It will sink, lowering the average height of the various heavy things in and on the canoe. Water will flow in.

If the canoe is made of light wood, which is a little less dense than water, it will end up floating deep in the water. If the canoe is made of aluminum, which is denser than water, it will keep sinking.

Mike W.

(published on 10/22/2007)

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