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Homework Help: Floats Above?

  1. Jan 26, 2009 #1
    A solid plastic cube with uniform density (side length = 0.5m) of mass 100kg is placed in a vat of fluid whose specific gravity is 1.2. What fraction of the cube's volume floats above the surface of the fluid?

    I couldn't figure this one out. I tried using the ration of SG's.
  2. jcsd
  3. Jan 26, 2009 #2


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    Per Archimedes principle, an object immersed in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the object. You can do the problem by ratios of the SG's, which gives the fraction of the cube's volume floating below the surface. Did you calculate the SG of the cube correctly?
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