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Time taken for energy to transfer ?

  1. Mar 25, 2010 #1
    Hello all.

    I'm currently looking at developing a realtime physics engine based on energy concepts. It will model all objects as soft-bodies but I need some source material that gives information on the time taken for energy to transfer between particles. I know that the transfer of this energy is not instantaneous, otherwise all bodies would be rigid (which they aren't), but, unfortunately, I cannot find any material that discusses such a concept.

    If you look at a golf ball being hit by a driver during a very small time interval, it is clear that the kinetic energy is transferred across the material not instantaenously, but incrementally. Different materials transfer this energy faster, or slower. Are there any books or papers that look at this in more detail? All I can find are extremely abstract analysis. No equations are offered.

    I appreciate any help.
  2. jcsd
  3. Mar 25, 2010 #2
    what you are talking about is material dependent. you wont find much online with regards to time based energy transfer. You could easily do average energy transfer over time, which would just be total energy divided by time in contact. There are extremely delicate tests that would need to be done. at different speeds, each material has a certain elasticity vs force kind of thing. and because you have two different materials colliding it would make it very very hard.
  4. Mar 25, 2010 #3
    Well in that case I'll have to use fake results based on intuition and observation. Since I'm aiming for plausibility, rather than realism, this should suffice.
  5. Mar 25, 2010 #4


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    Aren't you talking, basically, about the speed of sound in the materials? That's how fast the forces / energy are propagated through the objects.
  6. Mar 25, 2010 #5
    That's a very good observation.

    I may experiment with that idea and see if the results are anything near realistic.

    Edit: You are actually 100% correct with that. Many many thanks to you. Now I can finish the theory and start implementing it in code. If any of you are interested in viewing the model in realtime, I'll probably release a demo over the following months.
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