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Homework Help: If an object the size of the empire statbuilding had iron density,what would be .

  1. Sep 18, 2012 #1
    If an object the size of the empire statbuilding had iron density,what would be .....

    the mass of it?

    The estimated volume of the empire state building is 37 million cubic feet,how could I calculate the mass of this solid object if it had a density of Iron(which would be 7870 kg/m³)?
     
  2. jcsd
  3. Sep 18, 2012 #2

    HallsofIvy

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    Re: If an object the size of the empire statbuilding had iron density,what would be .

    Multiply the density by the volume.
     
  4. Sep 18, 2012 #3
    Re: If an object the size of the empire statbuilding had iron density,what would be .

    So I converted the ft^3 to m^3 and I have 1.04 million m^3* 7870kg/m^3=8184800000 kg/m^3.Did I do this right or do I have to remove the kg/m^3?
     
  5. Sep 18, 2012 #4
    Re: If an object the size of the empire statbuilding had iron density,what would be .

    Wow if I am correct is that over 8 billion kilograms of mass?
     
  6. Sep 18, 2012 #5
    Re: If an object the size of the empire statbuilding had iron density,what would be .

    So here is a follow up question,how much energy would be required to propel this object at Mach 7 speeds?
     
  7. Sep 18, 2012 #6
    Re: If an object the size of the empire statbuilding had iron density,what would be .

    1/2 mv2

    m=mass in kg
    v=speed in meters / second

    That would be if the propulsion device was 100% efficient and there was no air resistance.
     
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