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I violate law of energy conservation

  1. Jul 17, 2008 #1
    Let's say we have a helium balloon carrying total weight of 1 kg.
    We set up 2 stations. Pumping station on the ground and deflating station at certain height.
    We pump the ballon until it start to float up. We catch it at deflating station at height H.
    Now the energy we gain is potential energy of the falling balloon which is mGH.
    The energy require for pumping and deflating a ballon is set! If any.
    The height H can stretch as high as you want to! => mGH is a linear increasing function.
  2. jcsd
  3. Jul 17, 2008 #2


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    Staff: Mentor

    Cool -- perpetual motion finally!

    But seriously, if this is a closed cycle that runs continuously, how do you get the helium back down to the ground to keep refilling the balloon....? Pump it, right? And the energy you could get out of the balloon motion gets used up (plus more) in the helium pumping.

    Oh well, still no perpetual motion.
  4. Jul 17, 2008 #3
    Well, there's no problem in getting the helium back down. Just make a sealed tube that contain air lighter than helium and let gravity do the work. Yeah, still the sticky point is the pumping the ballon part. I suspect the energy require to pump the ballon is theoratically exact as the maximum height the ballon would reach. Oh well, I'll find another way to break that law.
  5. Jul 17, 2008 #4


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    Staff: Mentor

    Your time really would be better spent on another pursuit. Right now, you're playing a lottery with no jackpot!
  6. Jul 18, 2008 #5


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    I think we have entertained this sufficiently. Please review the https://www.physicsforums.com/showthread.php?t=5374" on why such topic of discussion is not allowed on here.

    Last edited by a moderator: Apr 23, 2017 at 2:20 PM
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