The envelope of the orbits of particles released with the same speed but in different directions from a point in an attractive or repulsive Coulomb field is studied with a simple geometric approach. The lawn sprinkler problem and the shadow of the repulsive Rutherford scattering are considered as the limiting cases.

中文翻译：

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从空间中的一个点开始的库仑轨道包络的几何方法

用简单的几何方法研究了从吸引或排斥库仑场中的一点以相同速度但在不同方向上释放的粒子轨道的包络线。草坪洒水器问题和排斥性卢瑟福散射的阴影被认为是极限情况。