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How can a true elasic collision exist?

  1. Feb 8, 2010 #1
    Is this something I just have to accept? How can there be no loss of energy/heat when I've always been taught otherwise. I imagine an elastic collision to be like the electromagnetic force field around an atom that just chimes when it hits another spherical force field around a different atom, like two wine glasses bumping together. Is this a good way to imagine it? Thanks in advance
  2. jcsd
  3. Feb 8, 2010 #2


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    There can't (although something like steel balls at normal lab speeds are pretty close)
    It's just one of those things like massless springs and friction free slopes that make it possible to see the main points
  4. Feb 8, 2010 #3
    Thank you, mgb, my intuition remains undefeated! Wikipedia almost had me convinced otherwise.
  5. Feb 9, 2010 #4
    If you can hear the collision, it is inelastic.

    Bob S
  6. Feb 9, 2010 #5
    Microscopic particles like gas atoms collide elastically.If the energy of collision becomes equal to or greater than an excitation or ionisation energy the collisions can become inelastic.
  7. Feb 10, 2010 #6
    Microscopic particles (like atoms or electrons) can easily collide elastically. This is a well known type of collision in nuclear physics. This is just a reflection that the particles must obey conservation of momentum and energy directly, with no "coefficient of restitution" or anything like that.

    If you're talking about macroscopic objects like balls, then elasticity is a thermodynamic property. In other words, any time you cause deformation in a macroscopic material, you have some kind of thermodynamic material property which causes a correlated production of heat and increases disorder among the molecules in the material. These byproducts like heat take away energy from the momentum. So, along these lines, you never have true elasticity in macroscopic objects.
    Last edited: Feb 10, 2010
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