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Relative Energy Generator

  1. Nov 14, 2009 #1
    I'm thinking that if you had a fan, rotating really really fast, then according to relativity the ends of the fan blades would think that the center of the fan has less energy than they do, and the center would think that the ends have less energy than it does right? So if this fan was made of a conductive material, then both the center and the ends would try to send energy to the other right? And if the center and ends had significant mass you'd be dealing with a huge difference in energy right? So then you could put something between the center and the ends and collect all of the energy they're giving off? Trick matter into giving up it's ridiculously large amount of energy. Possible?
  2. jcsd
  3. Nov 14, 2009 #2


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    Staff Emeritus
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    The short answer is no. It's true that the energy of an object depends on the frame of reference you are in. But the statement "has less energy than it does" doesn't make any sense. Things start to go downhill from there.
  4. Nov 14, 2009 #3
    If it's true that energy depends on the frame of reference, than why is it wrong to say "has less energy that it does"?
  5. Nov 15, 2009 #4


    Staff: Mentor

    There is no inertial frame in which the second part (highlighted in bold) is correct according to relativity. In all inertial frames the center has less kinetic energy than the ends. Also, in order to collect that energy you must slow the blades down, they don't just "give off" the energy without a decrease in their energy.
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