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B Energy states

  1. Nov 26, 2016 #1
    Does energy have different states analogous to the solid, liquid, gas, and plasma states of matter?
    Would they be the same as "forms of energy" described here?
  2. jcsd
  3. Nov 26, 2016 #2


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    Energy is not an object. It is a property of systems.

    "Does red taste like banana?"
    => both "is red" and "tastes like banana" are properties of objects, it doesn't make sense to ask a question like this.
  4. Nov 26, 2016 #3
    It makes sense to help correct a nonsensical preconceived notion.
  5. Nov 26, 2016 #4
    As mfb said energy is a property of a system and we talk about energy in many forms. Energy is any property of a system that could be applied to do work. Energy can either be potential or kinetic.

    Potential energy is energy of the configuration of the system. Some element of the system is poised to be moved by some force. A rock on the edge of a ledge has gravitational potential energy. It could fall off the ledge and do work under the force of gravity. A cocked nerf gun has elastic potential energy. The spring has been compressed and it can release that elastic energy and do work (in this case accelerating a dart). An unlit match has chemical potential energy. The ingredients are poised to react and release energy by changing their chemical bonding. Etc etc. Any force you can think of, there is a corresponding potential to do work.

    Then there is kinetic energy, the energy of an object in motion. A rock flying through the air could be caught and swing a pendulum or compress a spring to do some work. The flow of a river could turn a water wheel.

    Thermal energy is really just aggregate kinetic energy. The movement of all the molecules can be harnessed to do some work like pushing the piston in a steam engine.

    So Energy is a widely applied concept with many forms. Your linked article lists many of the forms. It probably isn't right to think of energy as a substance that has different phases. Energy is a property of a system. However we do often talk of converting one form to another or in the case of heat we talk of energy.
  6. Nov 26, 2016 #5
    You nailed what I was looking for, thanks!
  7. Nov 26, 2016 #6


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    And indeed he did!
  8. Nov 27, 2016 #7
    I was tired when I wrote that and apparently nodded off before I wrote the last word

    in the case of heat we talk of energy flowing.
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