In responce to fuzzybacon:
There is no loss of energy. If two particles collide, the total momentum stays the same. One particle transfers its energy to the other particle. No energy is created nor destroyed. If energy was destroyed, then when two particles hit each other, they would both be at a standstill. The only way something like that could happen is if friction was a factor, but the surface in which this game takes place is assumed frictionless.
So on far as physics goes, you don't know much about physics.
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