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Paper and pen challenge

  1. May 26, 2009 #1
    Hello ! My friend challenged me to remove a sheet that is under a standing pen, without the pen falling. I can only use 2 finger and i can only touch the paper. Do you know a way to do this ? (he said that I have to use physics)
     
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  3. May 26, 2009 #2

    turbo

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    What's the time-factor? If no time is specified and you remove the paper and the pen subsequently falls (even a fraction of a second later) you have done what was required.
     
  4. May 27, 2009 #3
    The pen is supposed to stay standing.
     
  5. May 27, 2009 #4

    QuantumPion

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    Did he give you a precise definition of "remove"?

    Got a match? :devil:
     
  6. May 27, 2009 #5
    There's a good chance fire won't solve this problem. If the pen conducts heat well enough, it might prevent the paper around it from burning by conducting the necessary heat away from it.
     
  7. May 27, 2009 #6
    Is this somehow similar to the "Cheers!" episode in which Norm puts a hat over a mug of beer and bets Cliff he can drink the beer without removing the hat. After Cliff accepts the bet, Norm gets under the bar and makes sucking noises like he's drinking the beer. Cliff says, "You didn't drink the beer." and lifts up the hat. Immediately Norm grabs the beer and drinks it.

    Can someone else hold the pen while you remove the paper?
     
  8. May 27, 2009 #7

    Danger

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    How on Earth do you get a pen to stand up in the first place? :confused:
     
  9. May 27, 2009 #8
    For a minute there I thought I was the only idiot who couldn't picture this! :biggrin:
     
  10. May 27, 2009 #9

    QuantumPion

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    :confused:

    I assume the pen has a cap with a flat surface.
     
  11. May 27, 2009 #10

    turbo

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    If the paper is a slippery playing card overhanging the edge of a table and you are able to give it a very quick snap, who knows? The more massive the pen and the larger the cap, the easier this might be.
     
  12. May 27, 2009 #11
    Make some magic motion with your hands around the pen. Then tell your friend the paper around the pen is gone and the pen is standing on the table. He won't believe you and lift up the pen. Then you grab the paper. Done! :P
     
  13. May 27, 2009 #12
    If you stand a pen on its point, it will fall over in about 15 seconds, due to the Heisenberg Uncertainty Principle, if I recall correctly the standing pencil problem in my QM course..
     
  14. May 27, 2009 #13

    DaveC426913

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    This is actually a perfectly valid solution. :approve:
     
  15. May 27, 2009 #14

    DaveC426913

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    Leave an edge of the paper hanging over the edge of the table.
    Grab the overhanging edge in one hand.
    Use your other hand to "chop" the paper between your hand and the table, pulling the paper out so fast that the pen stays stading.
     
  16. May 28, 2009 #15
    i dont think you just have to use physics for this, but you can use semantics. stand the pen on a tabletop. place the sheet of paper on the floor 'under the standing pen'.. then remove the sheet of paper. mission accomplished, the pen is still standing.
     
  17. May 28, 2009 #16

    DaveC426913

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    Good one. Though it depends on who gets to set the demo up. If he'll grant you the privilege then you can rig it that way.

    But if there were money riding on it I doubt he'd let you do the setup.
     
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