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Homework Help: Law of Conservation of Mechanical Energy

  1. Dec 26, 2007 #1
    [SOLVED] Law of Conservation of Mechanical Energy

    1. I was just questioning myself about why LCME won't work under the influence of non-conservational forces

    Could you go through my attached file I'd originally sent to my physics prof.? I have to wait a week before I meet him and get my answer and I'm not the pateint type and discussions of such types of questions are always interesting.

    Thank you,

    Attached Files:

  2. jcsd
  3. Dec 27, 2007 #2

    Andrew Mason

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    The Law of Conservation of Mechanical Energy is just a special case of the general law of conservation of energy. Mechanical energy is defined as the total kinetic and potential energy. So if some of that mechanical energy is transferred into some other form of energy (eg. heat or radiation) mechanical energy cannot be conserved.

    In a conservative field, the energy is always in the form of kinetic or potential energy. No kinetic or potential energy is lost (ie. kinetic energy is transferred only into potential energy and potential energy is transferred only into kinetic energy). Not so in a non-conservative field.

  4. Dec 27, 2007 #3
    Brilliant! Now why didn't I think of that?
  5. Dec 27, 2007 #4


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    The term "conservative force" in fact refers to a force that conserves mechanical energy. Gravitation and electromagnetism are examples; friction and fluid "drag" are non-conservative.
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