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What am I missing here?

  1. Jun 28, 2011 #1
    This is kind of similar to those troll science threads, but what am I missing here?
    6t4J4.png
    What if those energy-to-mass and mass-to-energy converters can reach 99.999% efficiency when converting to electricity to mass and vice versa in the future? Those converters are theoretically possible, aren't they?

    Note, this is obviously an oversimplified diagram. The wires are simply meant to represent the transfer of energy from one area to another, in this case, from an area of lower gravitational potential to an area of higher gravitational potential.
     
  2. jcsd
  3. Jun 28, 2011 #2
    The increased matter from restoring the substance to it's original potential is only relativistic. There is nothing new here and no acute efficiency over something such as a water wheel.
     
  4. Jun 28, 2011 #3
    I know it's probably nothing new, I just want to understand why it won't work. And I don't quite understand your answer. The matter never really increases, either, it just goes through a cycle of energy and matter. I guess you could say the matter increases every time the energy is converted the matter at the top, but I'm not sure if that's what you're saying.
     
  5. Jun 28, 2011 #4
    It will work but energy will be lost to heat.

    You can increase the relativistic mass of an object by "carrying" it to a higher potential, therefor converting energy to mass though it is only relativistic and reference frame dependent.

    The equation E = mc^2 is a relativistic equation.
     
  6. Jun 28, 2011 #5

    SteamKing

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    It's easier to convert a small mass into a large amount of energy than it is to convert a lot of energy into a small mass, given the technology currently available. Haven't you wondered why we are not using transporters to get around (a la Star Trek)?
     
  7. Jun 28, 2011 #6
    Nevermind how easy it is...

    I don't think you can actually convert energy (bossons) into rest mass (fermions).
     
  8. Jun 28, 2011 #7

    Drakkith

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    Due to losses the amount of energy generated would be less and less each time. Over time the amount of matter produced at the top is less and less until you have none. You would be turning the matter into energy, just like any fuel sorce does. This is all assuming you even have a device that can efficiently create and destroy matter.
     
  9. Jun 29, 2011 #8
    It is obviously very difficult for us to create and destroy matter right now. But let's say in 500 years we have something that can get extremely high efficiency. I don't see any reason why this would be impossible. I don't see any proof that there is a natural "cap" to the efficiency of these conversions.

    The wheel could theoretically make up for the energy lost on a machine with something even as low as 80% efficiency. Let's say the top part (energy-to-matter) was 20 miles above the ground part (matter-to-energy). They could be connected by superconducting wire. There could, again theoretically, be hundreds of these water-wheels more than making up for the 80% efficiency.
     
    Last edited: Jun 29, 2011
  10. Jun 29, 2011 #9

    I like Serena

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    I like your diagram. :smile:

    I think the question is: what happens if your make a current go up against gravity.
    Energy conservation would imply that the electrical energy is lost when going up against gravity (that is, it is converted to potential energy).
     
  11. Jun 29, 2011 #10
    Haha, thanks.

    I had thought of that, but couldn't you just transfer energy mechanically with gears or whatever, and maybe a motor-generator combo or something (assuming this is the future and the motor and generator are super efficient)?

    As in, just use a different method of energy transfer? Would energy still be lost this way? How?
     
  12. Jun 29, 2011 #11

    Drakkith

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    ANY work you got out of the device would reduce the amount of matter (and energy) that you had. This is because work requires energy. The whole process would be 1000 times simpler if you just took out all the other stuff and left in the matter to energy converter.
     
  13. Jun 29, 2011 #12
    Perhaps it inheres in the answers above, but:

    WHY does the matter get converted back to energy? If you matter generator is cranking out iron, it falls on the wheel, generates electricity, and you've got slower-falling iron.

    There's a part missing in your machine.
     
  14. Jun 29, 2011 #13
    Those converters are just meant to be obscure objects. The fact that the matter is slowed should have little to no effect.
     
  15. Jun 29, 2011 #14
    I think the scenario is (assuming 100% efficiency for the sake of the argument):

    You have an object on top, you let it fall on a sort of "waterwheel" except it isn't using water but rather it gets it's energy from the collision of the falling object. When the object is at the bottom, to raise it back up you would need as much energy as you got out of the falling object assuming 100% efficiency. But if you convert the object into energy and transfer it to the top using electricity or gears or something else and then convert it back into the object, would you lose any energy by transferring it like that assuming 100% efficiency? And if you would keep on repeating the process, would this sort of a machine be able to do work without requiring extra energy being inputted?
     
  16. Jun 29, 2011 #15

    Drakkith

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    No, you would lose energy by transferring it against gravity.
     
  17. Jun 29, 2011 #16
    Aha!...huh?

    I meant you've got slower-falling matter falling into the obscure energy converting machine.

    Where is the part that coverts the matter into energy to feed into the energy-converting machine?

    Please just add that to the other 2 obscure converters. One more won't do any harm.

    You can fool the rest of these guys, but not me.
     
  18. Jun 29, 2011 #17

    Drakkith

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    What do you mean dan? The bottom device converts matter to energy and the top converts energy to matter. I think it is just a representation of an actual device.
     
  19. Jun 29, 2011 #18
    Ah, you're right. I just superficially glanced at the E, and confused it for the input.

    OK, I'll buy stock.
     
  20. Jun 29, 2011 #19

    I like Serena

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    It's an interesting problem! :smile:

    If you would have a gear system running without transferring energy no energy would be lost.
    However, if you take out energy at the top, and pump in energy at the bottom (with for instance a dynamo and an electric motor), some of the energy must be lost due to conservation of energy (i.e. the conversion to potential energy).
    But exactly why that is? :confused:

    The fun thing is that if the gear system were horizontal, then no energy would be lost! :smile:
     
  21. Jun 29, 2011 #20

    Vanadium 50

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    It is. Think about it as electron flow and its obvious.
     
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