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Circle/Sphere touching

  1. Nov 28, 2015 #1
    Theoretically, if you had a perfect circle, and a perfectly flat surface, wouldn't only one atom touch at a time (assuming friction can't take away the perfect circle/flat surface)? Personally this doesn't sound right, but I can't think of why it wouldn't.
     
  2. jcsd
  3. Nov 29, 2015 #2

    A.T.

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    If they are made from atoms, how can they be perfectly flat or circular?
     
  4. Nov 29, 2015 #3
    What do you mean by "touch"? That term does not have a clear meaning at the atomic scale.
     
  5. Nov 29, 2015 #4
    As close as possible. I'm not very knowledgeable of physics, so feel free to explain.
     
  6. Nov 29, 2015 #5
    When I say perfectly round/flat, I mean as round or flat as atoms can get. I understand that because of the electron cloud, the round or flat part can never be the same.
     
  7. Nov 29, 2015 #6

    Nugatory

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    Then you've answered your own question. "As round or flat as atoms can get" is not the same thing as "perfectly exactly geometrically round or flat" so you already know that you cannot reason about this system as if it were perfectly flat and perfectly round.
     
  8. Nov 29, 2015 #7
    What is the difference?
     
  9. Nov 29, 2015 #8

    davenn

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    reread you own answer in post #5


    Dave
     
  10. Nov 30, 2015 #9

    russ_watters

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    So....as round as atoms can get means that on the atomic scale, the circle looks pretty flat, just as the round earth looks pretty flat to our eyes.
     
  11. Nov 30, 2015 #10

    A.T.

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    If you understand that on the particle level you just have electron clouds, wobbling atoms and varying force fields, then you should see how pointless it is to ask questions based on idealized geometric shapes.
     
    Last edited: Nov 30, 2015
  12. Nov 30, 2015 #11

    CWatters

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    +1

    http://sciencequestionswithsurprisinganswers.org/2013/04/16/do-atoms-ever-actually-touch-each-other/

     
  13. Nov 30, 2015 #12

    A.T.

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