I'm stuck on a practice problem for physics (and I have a test tomorrow afternoon!) A small sculpture made of brass (ρ = 8470 kg/m3) is believed to have a secret central cavity. The weight of the sculpture in air is 15.76 N. When it is submerged in water, the weight is 13.86 N. What is the volume of the secret cavity? I think this problem involves Archimedes’ Principle (Fbuoyant = Wdisplaced fluid ). And I know W = ρ*V*g. The density of water is 1000 kg/m3. I know the answer to the problem is 4 x 10-6 m3. I just do not know how to get that answer because everything I come up with is wrong! I tried plugging in the weight of water, density of water, and gravity and solving for the volume displaced. Then I did the same thing with the weight of the sculpture in air, density of brass, and gravity and solving for the volume of brass. Then I subtracted that volume from the volume displaced by water… and came up with the wrong answer! I would appreciate any help! Thanks!