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Kinetic Energy

  1. Mar 25, 2008 #1
    We all know the theory that energy never dies, that it is only transformed into a different type of energy.
    Well, I was wondering, when kinetic energy is absorbed by an item, what happens to the energy? If the kinetic energy is not transfered to the object, but absorbed, then where does the energy go?
  2. jcsd
  3. Mar 25, 2008 #2
    deformation or potential energy
  4. Mar 25, 2008 #3
    I'm not sure what you mean by kinetic energy being "absorbed". Kinetic energy is the energy of movement.
  5. Mar 25, 2008 #4
    If an item that has kinetic energy impacts something with no kinetic energy and the item that is impacted does not move, then the kinetic energy is absorbed.

    In other words: If a boulder is falling off of a cliff and it hits a gigantic mass of marshmallows, the marshmallows would absorb the boulder's remaining kinetic energy causing the boulder to stop.

    So tell me, what happened to that absorbed kinetic energy?
    I do not think it becomes potential energy because potential energy is characterized by how much an object is prone to have kinetic energy (or how much an object is prone to fall down).
  6. Mar 25, 2008 #5

    Doc Al

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    Staff: Mentor

    The macroscopic KE will be transformed into a combination of deformation, potential energy, and internal energy (random motion of the molecules). (And maybe even a bit of sound energy.)
  7. Mar 25, 2008 #6
    That was a really good description, I think that answers my question well enough. :D
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