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Buoyance of oil and water

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  • #1
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I have 2 liquids, Oil and water together in the beaker.

Assuming both liquids are non mixable

I push a block into the water and it floats at halfway between the Oil and the water

See the attachment and please help me I'm stuck and
passing the class depend on this particular problem ...
 

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Answers and Replies

  • #2
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Do you about Archimedes principle ? A body floats at the level where the weight of the submerged part equals the weight of the displaced liquid.

I think you got your specific gravities the wrong way round.
 
  • #3
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Do you about Archimedes principle ? A body floats at the level where the weight of the submerged part equals the weight of the displaced liquid.

I think you got your specific gravities the wrong way round.
Yes I'm talking about Archimedes principle..

The Professor gave us this question as it is.. ireally tried to resolve it without
any success. any suggestions??
 
  • #4
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Mentz pointed out one problem. Another, even if reversed, Water has an sg=1.0, not .3 or .8

Finally as posed and assuming that the block is homogeneous and density greater than either fluid, the object would sink. I'd put this one away until you get clarification.
 
  • #5
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Mentz pointed out one problem. Another, even if reversed, Water has an sg=1.0, not .3 or .8

Finally as posed and assuming that the block is homogeneous and density greater than either fluid, the object would sink. I'd put this one away until you get clarification.
I'm sorry it is not water the question was two liquids.
Any liquids. assuming they are 0.3 0.8 i used water and
oil just to clear out which one is on the top and which
one is on the bottom.
So ignore the names.
The question didn't say anything about the object's density
the question only wants to know the % of the part that is
in the oil..
 
  • #6
5,428
291
My reading of the question is that the block has sg = 0.93. So it would sink in the more dense liquid if it wasn't partly supported by the upper liquid.

Assume the block sinks to a depth x, and has top area A. You get an equation in x because A will cancel out.
 
  • #7
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maybe this is a deep problem after all, but the diagram shows a density greater than either fluid, but adds to it "in water part". If the density is greater than either fluid it will sink as in completely. Now if the density were somewhere between the two, ok, it should sit in between. But whats most confusing is you state that the object is 1/2 in 1/2 out, but the diagram asks for what percentage is in the oil? I personally (and this is without any mean spirited intention), is that you probably should repeat the course. Our bailing you out at the last minute is not apt to be of value to anyone.
 
  • #8
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Can Any One Help me with this Question????
 
  • #9
by the looks of that picture ( 50%) heh
 
  • #10
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Help anyone
HELP
SOS
 
  • #11
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help
help help
help
 
  • #12
sorry, I wish I could help, but never took fluids yet. I agree with zenparticle though:shy:
 

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