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How many atoms per meter are there in a carbon nano tube?

  1. Apr 26, 2012 #1
    I'm interested in the theoretical minimum number, so like the extruded buckyball ball?

    I'm trying to work out if there are enough carbon atoms in a 'piece of paper' to reach the moon. :)

    Which brings me to the next question : how many carbon atoms are there in a piece of paper? Or perhaps a better way of putting it would be, how big a piece of paper would you need - would a sheet of A4 paper get you there?

    This all comes from me coming across that idea that if it was possible, you'd only have to fold a piece of paper 44 times to reach the moon! ie by doubling the thickness 44 times, you'd exceed the distance from the earth to the moon.
  2. jcsd
  3. Apr 27, 2012 #2


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    Staff: Mentor

    This is just a geometrical problem. Nano tube is a repeating pattern, find the "building block" - number of atoms, length - and then it is trivial.

    Note that carbon nano tubes can have different radii, so the number of atoms depend on the properties of the particular tube.
  4. Apr 27, 2012 #3


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    Gold Member

    That would be
    Distance = thickness pf paper x 2^44
    So that is easy to calculate.

    Size of paper:
    You can calculate the size of paper needed by knowing: ( best to start off with a square piece of papaer )
    A carbon aom has a diameter of 0.22 nm ( 2,2 x 10^-10 m )

    And that on each second fold, or folds of even powers of 2, result in another square ( odd folds have a rectangular shape )

    So is A4 paper large enough or are you trying to fold an atom???
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