Mass of displaced water?

Question

I just have a little question. I'm working on a packet in my physical science class. We just started getting into water displacement and I'm very confused.

So, as long as I'm following the information we're learning, then the amount of water displaced is going to be equal to the volume of the object submersed?

Well, my question is this: is the mass of the water displaced also equal to the mass of the object, or no? And if not, then how do I find the mass of the displaced water?

((The given example was of a wooden block with a mass of 5000g and a volume of 1000cm3. I figured that it displaces 1000mL of water, and I need to determine the mass of the water displaced. I suppose it's also 5000g, but is that wrong?))

Answer 1

You can't really figure out the mass of a 1000 mL of water unless you know the temperature or density of water. Usually we use the value 1.0 g/mL for the density of water so I suppose you could use that value but then you'd be making the assumption that the water is in within a temperature range such that it's density is 1.0 g/mL. That assumption may not be correct but with the information given that's all you can do if you must absolutely find the mass of the displaced water.



So anyways, if we assume that the density of water is 1.0 g/mL then the mass of a 1000 mL of water is 1000 g.



Density=mass/volume

1.0 g/mL=mass/1000 mL

mass= 1.0 g/mL x 1000 mL=1000 g

Answer 2

there is no relation between the mass of the water displaced and the mass of the object



once an object is denser than water, it will displace the same amount of water no matter how massive it is (I mean a denser mass in the same volume)



if the object floats, however, you can determine its relative density to water by seeing what percentage of it has sunk.



this assumes the object is 'convex' (like a block a wood) with no holes in it (like a boat has)



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so the density of your example is 5000/1000 or 5. where the density of water (in the same units) is?



in any case, if the block sinks, you're out of luck, but if it floats, then note what percentage of it is 'under water'



You then know the underwater portion of the block (percentage times total volume of the block) is the volume of water needed to counterattack the full weight of the block (otherwise, gravity would continue pulling it down)



which is a fancy way of saying 'if the block floats, the mass of the displaced water is 5000g, the mass of the whole block'



that doesn't sound like something they would be asking, however.



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If we assume the density of the water is 1, then the block (density 5) will most definitely sink to the bottom, at which time the volume displaced will be the volume of the mass. 1000 and the mass of that much water will be 1000 * 1 or 1000. No matter what the density of the block was, so long as it was greater than 1g/cm.



seems like a weird question though.

Answer 3

a rock @ 126 gm will displace how much water

Answer 4

WHAT IS THE FORMULA?