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Is this a eureka moment? .how do we know atoms exist?

  1. Apr 16, 2015 #1
    just picture what happens when you fill a 2 liter soda bottle with water (or any liquid) and try to pour it all out at once. it comes out in clumps. This means there will be competition, since all the water will try to escape all at once. the fact that there is competition means that there must be more than one seperate entity competing. if there were no spaces between the atoms, the water would all flow out uniformly and consistently. and I suspect, - maybe - , that the time intervals between clumps can be measured by avocadro's number and, in turn, can MEASURE avocadro's number.
     
  2. jcsd
  3. Apr 16, 2015 #2
    The separate entity competing is just air trying to get in to the bottle to replace the liquid which drained out.
    The rate at which it does so will be related to the diameter of the drain hole amongst other factors, such as the viscosity of the fluid.
     
  4. Apr 16, 2015 #3

    SteamKing

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    It's Avogadro's Number, not avocado's number. That's some kind of fruit.
     
  5. Apr 16, 2015 #4
    that's not correct
     
  6. Apr 16, 2015 #5
    my explanation is still valid
     
  7. Apr 16, 2015 #6
    I said avocadRo's number
     
  8. Apr 16, 2015 #7

    DrClaude

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    You can fully study and understand this kind of fluid dynamics without referencing the existence of atoms. It is not a proof of the existence of atoms.
     
  9. Apr 16, 2015 #8
    you still didn't answer the question. why doesn't the air push all the liquid out in a uniform flow?
     
  10. Apr 16, 2015 #9
    just tell me why my explanation is wrong
     
  11. Apr 16, 2015 #10

    DrClaude

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    The air doesn't push the liquid out. The liquid is being pulled out by gravity and air must full the low pressure volume left by the moving liquid for the liquid to continue to pour out.

    Why?
     
  12. Apr 16, 2015 #11
    ok. I never said that gravity doesn't pull the water out. why doesn't gravity pull the water out uniformly and consistently?
     
  13. Apr 16, 2015 #12
    why can't you just admit that this is a eureka moment?
     
  14. Apr 16, 2015 #13
    What?, you have discovered that pouring liquid out of a bottle results in a bottle full of air?
     
  15. Apr 16, 2015 #14

    DrClaude

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    Because then air couldn't get in to fill the void being created.

    This site is for discussing science. Your "eureka moment" is in no way a demonstation of the existence of atoms.
     
  16. Apr 16, 2015 #15
    give me a valid explanation for why it's not a demonstration for the existence of atoms. you can't just say it without an explanation.
     
  17. Apr 16, 2015 #16
    that sarcastic comment didn't answer anything. I know that air fills the bottle as the water is pouring out. why does the water come out in clumps?
     
  18. Apr 16, 2015 #17
    the fact that air can get in doesn't prove my explanation wrong. as the water leaves, air takes its place.
     
  19. Apr 16, 2015 #18

    DrClaude

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    You simply have a fluid that splits up. You don't need atoms for that.

    I quote you again:
    That's a non-sequitur. It's up to you to prove that the conclusion follows from the premise.

    Because otherwise the water blocks the air from coming in. If you take the bottle upside down and turn fast to create a vortex, you will see all the water flowing out continuously.
     
  20. Apr 16, 2015 #19
    It could be explained by complex fluid dynamics (both the liquid and the air are fluids)
    In rough terms, an oscillation is being set up in which some fluid flows out, then some air flows back in.
    The exact frequency of that oscillation will involve many factors including atmospheric pressure, the density of the liquid, the diameter of the drain, hole, the geometry of the bottle and probably a lot more, but it's computable in principle, given a bit of chaos theory to mix up up things a bit.
     
  21. Apr 16, 2015 #20
    just agree with drclaude
     
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