Musings on Free Energy

Discussion in 'Physics' started by studiot, Sep 14, 2009.

  1. studiot

    Thread Starter AAC Fanatic!

    Nov 9, 2007
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    It is well known that infinity minus one (or minus a 100 or 1000) equals infinity.

    So if we can find an infinite souce of energy and take some away .......we still have an infinite source of energy and some!

    Now that may seem a might trite so chew on this.

    Einstein teaches that the speed of light is the same for all observers.

    So let us bounce some light off an object, transferring some of the photons' momentum to it.

    The 'bounced light' still has the same speed and therefore energy, but the object has 'gained' some momentum.

    Is this a potential source of free energy?
     
    Last edited: Sep 14, 2009
  2. Papabravo

    Expert

    Feb 24, 2006
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    So how much energy is transferred in each collision?
     
  3. beenthere

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    Apr 20, 2004
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    Nope - the photons carry energy in the frequency of light they transport. When they bounce off in an inelastic collision, they will have the same momentum, but their energy will be less as demonstrated by a redder color. The object will be warmer by the difference in the pre- and post collision energy of the photons.
     
  4. Skeebopstop

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    Jan 9, 2009
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    That is exactly right. A practical example would be the thermodynamics of spaceheating. Once upon a time I was watching star trek and asked myself how for example, a switch mode power supply operating in the vacuum of space would cool its MOSFET for example. I then followed that thought onto how the entire ship and thrusters would do the same as they burn fuel when there are no 'particles' in the vacuum to 'bounce' your energy into and thus cool.

    The answer boiled simply down to, all heating and cooling in spacecraft (externally) must take place via electromagnetic absorption/emission. The poor engineers who have to do their thermal modelling for space grade heatsinks!! Makes me wonder if they don't specially design heatsinks which excite when heated and emit light instead of physical heat to help get that heat energy out of the component of cooling. I suppose a material that 'glows' red hot would be a great space grade heatsink.
     
  5. Wendy

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    Mar 24, 2008
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    I remember a scifi book that used something called cooling lasers, they used the excess heat and dumped it with lasers. Not likely, but barely possible. Using extra energy to pump other energy around you can dump it other ways.
     
  6. beenthere

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    Not SF. The Bose-Einstein condensate of atoms that occurs when the local energy is low enough can and has been achieved by using lasers to extract energy from a gas.

    Here is a link - http://www.colorado.edu/physics/2000/bec/
     
  7. Wendy

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    The book in question was Sun Diver, by David Brin. The idea was a station on the surface of the sun (artifical gravity is also a must). To keep the station cool they pumped the excess energy out in the form of lasers.
     
  8. Skeebopstop

    Active Member

    Jan 9, 2009
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    MOSFETs aren't a gas :)
     
  9. Skeebopstop

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    Jan 9, 2009
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