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Homework Help: Xeno is a spherical planet with a diameter of 2160 Kms

  1. Jun 20, 2005 #1
    Intelligent beings on the plantet Xeno have developed a unit of distance called the xen.

    The number of square xens in the surface area of Xeno is exactly the number of cubic zens in its volume.

    If Xeno is a spherical planet with a diameter of 2160 Kms, how many km are there in one Xen.

    The Answer is 360, but i am confused with the method.

    thanks..
     
  2. jcsd
  3. Jun 20, 2005 #2
    Start by figuring out the surface area's equivalence to the volume. The planet is a sphere..
     
  4. Jun 20, 2005 #3
    ok, heres wat i got i dont know if this it right though?

    Let n be the number of square or cubed xens
    let x be the number of xens

    n(1)=n(2)

    n(1)x^2= 4 (pi) r^2
    n(1)=4(pi)r^2/x^2

    Simariarly, volume

    Is that correct?
     
  5. Jun 20, 2005 #4
    I'm not really sure what you're doing. The first thing I'd do is figure out the planet's surface area and volume in km.
     
  6. Jun 20, 2005 #5
    i did that you get huge numbers

    i'll write it
    N one= N two (given)

    N one time x squared= 4 pi r^2
    N one= 4 pi r^2 divided by x^2

    Is that correct>?
     
  7. Jun 20, 2005 #6
    Hello? help!...................
     
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