两小球弹性碰撞理论推导设两个小球发生弹性碰撞根据动量守恒定律,11221122mvmvmvmv(1)根据弹性碰撞过程机械能守恒,22221122112211112222mvmvmvmv(2)由(1)式移项,得11112222mvmvmvmv(3)由(3)式,得111222mvvmvv(4)由(2)式移项,得22221111222211112222mvmvmvmv(5)由(5)式,整理得1111122222mvvvvmvvvv(6)将(4)式代入(6)式左边,整理得1122vvvv(7)由(1)和(7)式,解得12211212122mmmvvvmmmm(8)21122121212mmmvvvmmmm(9)