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Homework Help: Pressure And Buoyant Force Hw problems

  1. Nov 5, 2011 #1
    1. The problem statement, all variables and given/known data

    1) A 0.0200 kg metal(density=4.000 g/cm^3) object is suspended from a thead and is submerged in a jar of oil(density=1.500 kg/dm^3) What is the apparent weight in the thread) For this one I keep doing this one but I think Im getting it wrong because of my conversion

    2)A metal cylinder has a voluem of 2150 mm^3. Find the buoyant force when it is completely submerged in a liquid that has a density of 0.900 kg/dm^3 For this one Idk y my answer is wrong but can someone explain 2 me cuz I think this one I'm getting wrong because of my units but please show me the steps on how 2 solve this problem
    2. Relevant equations



    3. The attempt at a solution

    1)(1500 kg/m^3)(40 kg/m^3)(9.80 m/s^2)

    2)(800 kg/m^3)(2.150 m^3)(9.80 m/s^2)
     
    Last edited by a moderator: Nov 6, 2011
  2. jcsd
  3. Nov 6, 2011 #2

    rude man

    User Avatar
    Homework Helper
    Gold Member

    First, 4g/cm^3 does not equal 40 kg/m^3.

    Second, you need the denssity of your oil.

    Third, read about that old Greek, Archimedes.
     
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