平动及其在起潮力中的作用

TRANSLATION AND ITS FUNCTION IN TIDE-GENERATING FORCE

在讨论日月起潮力时 ,可以不考虑地球的自转。把地球绕地月公共质心的运动直接看成平动是完全合理的。给出了在平动前提下 ,地球表面或地球内部任意一点在随地心绕地月公共质心作圆周运动时的轨迹方程 ,从而从数学上论证了可以把地球任意一点的起潮力定义为天体 (月球或太阳 )对该点的引力与地心引力的矢量差 ,既简明又抓住了起潮力的本质。

The rotation of the earth can be neglected while discussing the tide generating force, it is reasonable that the orbit motion of the earth round the common mass center of the earth with the moon can be considered as a translation. Under the presupposition of the translation, the locus of any point on or inside the earth was given. It was mathematically proved that the tide generating force on any point located on or inside the earth can be defined to be vector difference between the gravitational forces on the point from celestial body(Moon and Sun) and the mass center of the earth,this definition is simple and reflects the nature of tide generating force.