LOL i just posted a question EXACTLY like this. Anyways, I understand arctans arguement, but I don't know where you would add the pressure pushing back from the other side . . .
This one is a doozy . . .
A fresh water pond that is 15.7 m deep is contained on one side by a cliff. The water has eroded a nearly horizontal "tube" through a bed of limestone, which allows the water to emerge on the other side of the cliff. If the "tube" has a diameter of 4.05 cm, and is...