A metal cube rests on the bottom of an empty vessel. Water is then poured in until the cube is completely submerged. The downward force on the part of the vessel bottom that is in contact with the cube will

will increase
will decrease
will remain the same
will become zero

Correct answer: will increase

Solution

With the cube sealed against the bottom, water pressure acts on the top (downward) but not underneath, so there is no buoyancy to lift it. The extra downward pressure on the top increases the force on the bottom under the cube.

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