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I have a question about conservation of energy

  1. Feb 16, 2015 #1
    I have a question about conservation of energy...

    So, I have a question about conservation of energy. I just want a detailed example of the path of the energy in some regular scenarios and the reach of it.

    For example...

    When playing pool, the cue ball is shot at a stationary 8 ball. The cue ball now has kinetic energy. When the cue ball hits the 8 ball, the kinetic energy transfers from the cue ball to the 8 ball, sending the 8 ball into motion. The cue ball loses energy because the energy it had has been transferred to the 8 ball, so the cue ball slows down.

    So, now the 8 ball is in motion and then it hit a wall from the pool table and it stops. What happened to that energy?

    I mean, I often see examples showing a simple transition.

    Can you please describe more energy transitions in that example... let's say... 10?

    EDIT: Sorry for my English... not my primary language.
     
  2. jcsd
  3. Feb 16, 2015 #2
    The 8 ball hit an elastic object that absorbed the energy over a longer time then bal-ball inelastic collisions.
     
  4. Feb 16, 2015 #3
    motion of the molecular components.
     
  5. Feb 16, 2015 #4
    For example...

    Energy from the cue stick > kinetic energy to the cue ball > kinetic energy to the 8 ball > energy transferred to the wall of the pool table? What kind? > ? > ? > ?
     
  6. Feb 16, 2015 #5
    kinetic energy of the molecular components. Just think of the wall as it is composed with a huge number of billiard balls.
     
  7. Feb 16, 2015 #6
    OK. Then what happens to that kinetic energy of the molecular components?
     
  8. Feb 16, 2015 #7
    since energy is conserved and from thermodynamics we can say that this is equivalent to saying that we increase the temperature of the wall. This motion of the molecules is then eventually transfered to the environment. The details can be argued from a field called statistical mechanics.
     
  9. Feb 16, 2015 #8
    All energy transfer results in heat. Take the original kinetic energy equate it to heat then subtract each collision. The final result is the heat death of the universe. Entropy will not be denied.
     
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