“接地”是高中物理中常用的一个术语,一般情况下,认为接地点的电势为零.也有学生提出:“电流流入大地时有没有电阻?如果有电阻,在电流流入大地的过程中一定会有电势的降落,大地各点的电势将不相等,究竟哪一点的电势为零?”这样的问题,教师往往用:“大地可以认为是截面积无穷大的导体,所以电阻为零.”来搪塞.可事实是这样吗?本文以接地的导体为半球状这一特殊情况为例来讨论和接地有关的几个问题. “Ground ” is a commonly used term in high school physics, under normal circumstances, that the potential of the ground point is zero.Also some students put forward: “Current into the earth when there is no resistance? If there is resistance, the current flows into the earth There must be a potential drop, the potential of the earth will not be equal, which point of the potential is zero? ”Such a problem, teachers often use: “ The earth can be considered as a conductor of infinite cross-sectional area, so the resistance is Zero. ”Can be stalling. Can it be the case? In this paper, the grounding of the conductor is a hemispherical special case to discuss several issues related to the ground.