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- How does buoyancy work? 5 answers
I was reading about how to find the buoyancy force when I came across this explanation:
Imagine a box submerged in a tank of liquid.
The distance from the surface of the liquid to the bottom surface of the box is greater than the distance from the surface of the liquid to the top surface of the box. In short, $h2 > h1$.
Because $p = \rho g h$, the pressure on the bottom surface due to the liquid must be greater than the pressure on the top surface. This results in there being more force on the bottom surface of the box than there is on the top surface.
The difference between these two forces causes there to be a net force upwards called the buoyancy force.
I understand how the force acting downwards onto the top surface of the box is found. This is simply due to the column of water above the box. But how is the force acting upward onto the bottom surface found?
I specifically want to to understand where the force acting onto the bottom surface of the box, upwards, derives from.