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A question on the conservation of energy

  1. Feb 13, 2005 #1
    Hello all. Please help me find the answer to my question...I would glady appreciate your help.

    I'd like to know...since the conservation of energy states that energy can neither be created nor destroyed but only gets tranforms from one form to another, how is it that we today already have energy sources etc. around?

    I mean, as in, like the sun's energy and the energy that's being used to power this computer and so on...where did those energy come from if the law states that " energy........cannot be created nor destroyed..."?
     
  2. jcsd
  3. Feb 13, 2005 #2

    dextercioby

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    For the first part,the simplest example i can think of is the one with wind-mills:we thake the energy of air flows (wind) and use it to produce (very cheap) electrical energy...Sure,there may be loses,but that is a good example of energy conservation & "energy sources" involved.

    As for our Sun,it "burns out fuel" continuously and it's estimated that it will exhaust it in ~5 billion yrs...

    And the energy powering our computers comes from "energy sources" which are based on the same fundamental principle.

    Daniel.
     
  4. Feb 13, 2005 #3
    so what made the wind? what made the air that constituted the wind? And so on...
    how did the sun have that fuel to burn?

    does " because the big bang happended" answers my question?
     
  5. Feb 13, 2005 #4

    dextercioby

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    Sure,this chain of question would indeed end with the question:"Where did everything come from",if this everything is generally conserved...
    So for the last question,the answer is that BB happened in the SM-based version of cosmology.

    Daniel.
     
  6. Feb 13, 2005 #5

    arildno

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    There is an on-going, irreversible process of depletion of useful types ofenergy in the universe.
    This is called the 2.law of thermodynamics.
    (The 1.law states that all (useful plus useless) energy is conserved)
     
  7. Feb 13, 2005 #6
    what is SM-based version of cosmology???
     
  8. Feb 13, 2005 #7

    dextercioby

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    The origin (fuzzy) and the evolution of the Universe viewed by the cosmologists using The Standard Model of Particles and Interactions...

    Magnificiently described by (Nobel Laureate) Steven Weinberg in his book:"The First Three Minutes"...

    Daniel.
     
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