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Homework Help: Fluids Question

  1. Apr 17, 2010 #1
    1. The problem statement, all variables and given/known data
    An object weighs 285 N in the air. When tied to a string, connected to a balance, and immersed in water, it weighs 230 N. When it is immersed in oil, it weighs 261 N.

    (a) Find the density of the object.

    (b) Find the density of the oil.
    2. Relevant equations


    3. The attempt at a solution

    this weight is equal to 285-230=55N corresponding to a density =1
    so the density of the body is 285/55=5.18

    the weight of oil is 285-261= 24 =Mgd(oil)
    compared to water d(oil)/d(water)=24/55=0.436
  2. jcsd
  3. Apr 17, 2010 #2
    Your answers are correct, but you should write down the units.
  4. Apr 18, 2010 #3
    I believe my answer is wrong. If someone would double check it.
  5. Apr 18, 2010 #4
    I did double check it when I first posted. Your answers are right but missing units. If your teacher wanted different units then perhaps therein lies your confusion.
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