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Energy is

  1. Sep 25, 2005 #1
    I have heard one definition of energy meaning a degree of inertial resistance... can anyone give me a different working condition for the word
  2. jcsd
  3. Sep 25, 2005 #2
    Degree of inertial resistance sounds more like mass to me.... *shrug*
  4. Sep 25, 2005 #3
    In physics, energy is the capability of something to do work. And yes, a "degree of inertial resistance" is mass.
  5. Sep 25, 2005 #4
    yea degree of inertial resistance does sound like mass. but mass is energy according to E=MC^2 so i guess its right in a way. my pinky is energy along with my text book and keyboard
  6. Sep 26, 2005 #5
    Matter is not energy, matter can become energy and vice vesa.
  7. Sep 26, 2005 #6


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    I'm not quite in agreement with that, but it might be just a matter of me using the wrong terminology. Given the wave functions involved, I always consider matter to be energy in a bound state, roughly analogous to ice being water in a bound state.
  8. Sep 29, 2005 #7
    Matter IS.... another form of energy or vice versa
  9. Sep 29, 2005 #8


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    "Energy" is a bookkeeping device (how many words do you know with three double letters in a row?). People noticed long ago that kinetic energy is conserved in simple collisions so developed "conservation of energy". Of course, if the collision is not "elastic" that doesn't work so they added "heat" as a type of energy to "explain" that (and keep "conservation of energy" true). When relativity made it clear that mass could be converted to energy (and vice-versa) mass itself was declared a kind of energy just to make "conservation of energy" still work!
  10. Sep 29, 2005 #9
    The term Inertial resistance has never been defined in physics. Let me offer this;

    inertia is defined as the amount by which a body resists changes in momentum. So what would you call something which resist a change in momentum? I'd call that "force" in that F = dp/dt.

    The definition of energy is given here


  11. Sep 29, 2005 #10


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