If an egg rolls end over end along a horizontal surface, its centre of mass rises and falls. Four different rolling modes are described, namely pendulum oscillations, falling from rest, rolling without slipping and jumping in the air. Supplementary videos are provided for each type of motion, together with a theoretical analysis. The results in each case depend on the initial conditions and the coefficient of sliding friction. The motion of a rolling egg is analogous to the motion of a loaded hoop, and falling motion is analogous to the fall of a rod or a pencil.

中文翻译：

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滚动鸡蛋的动力学

如果一个鸡蛋沿着水平面翻滚，它的质心就会上升和下降。描述了四种不同的滚动模式，即钟摆振荡、静止坠落、滚动而不滑倒和空中跳跃。为每种类型的运动提供了补充视频以及理论分析。每种情况下的结果取决于初始条件和滑动摩擦系数。滚动鸡蛋的运动类似于负载箍的运动，而下落运动类似于杆或铅笔的下落。