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Homework Help: Block floating in water - Oil is added

  1. Jun 18, 2008 #1
    1. The problem statement, all variables and given/known data
    A block of wood floats on water. A layer of oil is now poured on top of the water to a depth that more than covers the block.If 75% of the wood is submerged in water before the oil is added, find the fraction submerged when oil with a density of 715 kg/m3 covers the block. (Do not neglect the buoyant force of air before the oil is added.)



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Jun 18, 2008 #2
    Hey emenos,
    The fraction of the block floating initially is given. Get the density of the block from this assuming Dwater=1000kg/m^3. Once you get the density use archimedes principle and newton's 2nd law to get the required fraction.
     
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