Bouyant force on a cube floating at the surface between water and oil?

  1. 1. The problem statement, all variables and given/known data
    A cube of 15 cm is floating at the surface between water and oil. The oil has a density of 810 kg/m3. If the cube floats so that it is 52% in water and 48% in the oil, what is the mass of the cube and what is the buoyant force on the cube?


    2. Relevant equations
    Archimede's Principle
    Fb= densityfluidvfluidg



    3. The attempt at a solution
    Not sure how to find the mass of the cube when only the height of one side is given?
     
  2. jcsd
  3. mgb_phys

    mgb_phys 8,952
    Science Advisor
    Homework Helper

    Chegg
    The cube is displacing it's own weight in oil and water.
    it might be simpler to think of it as two (almost ie 0.52/0.48) half cubes immersed in oil and water.
     
  4. fb = (1000*0.52+810*0.48)*0.15^3*9.8
    =30 N

    mass=fb/g
    =30/9=3.33
     
Know someone interested in this topic? Share a link to this question via email, Google+, Twitter, or Facebook

Have something to add?