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I understand that pressure increases with depth in a liquid and that it is the difference in pressures at the top and bottom of an object submerged in a liquid that provides the buoyant force. What I do not understand is how the liquid exerts a pressure on the bottom of a completely submerged object. Isn't all the liquid displaced at this point? (No liquid remains underneath the object???) And if the pressures exerted horizontally are equal and opposite, it seems there is a net pressure directed downward. How then is the buoyant force still dependent on pressure differences and directed upward?