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- Homework Statement
- I have a problem with understanding the solution of the problem below. At the beginning, there is a formula for the speed of water streaming inside the boat. But I don't know how to calculate it.

- Relevant Equations
- ##v=\sqrt{2g(h_2-h_1)}##

The problem:

Its solution:

I am sure that the velocity ##v## can be calculated by using Bernoulli's equation, but I fail to calculate it.

I don't know what pressure is at the hole - is it ##h_2 \rho g## or ##(h_2 - h_1) \rho g##? The pressure of the water "under" the hole is ##h_2 \rho g## and the pressure just "above" the hole is ##h_1 \rho g##. So what is the pressure at the hole? Is it its difference?

And I am also a little bit surprised that I can calculate the buoyancy when there is a hole in the boat. I thought it could be calculated only when the submerged body is without holes - when a liquid is only around the body, not inside of it. Why can I ignore the holes and calculate the buoyancy as if there were none?

Its solution:

I am sure that the velocity ##v## can be calculated by using Bernoulli's equation, but I fail to calculate it.

I don't know what pressure is at the hole - is it ##h_2 \rho g## or ##(h_2 - h_1) \rho g##? The pressure of the water "under" the hole is ##h_2 \rho g## and the pressure just "above" the hole is ##h_1 \rho g##. So what is the pressure at the hole? Is it its difference?

And I am also a little bit surprised that I can calculate the buoyancy when there is a hole in the boat. I thought it could be calculated only when the submerged body is without holes - when a liquid is only around the body, not inside of it. Why can I ignore the holes and calculate the buoyancy as if there were none?