如何确定静电场中各点电势的高低,是教学中的一个难点。笔者经过多年的教学实践,总结出了下述简捷易行的四条方法,就是中下等程度的学生也能掌握,兹将此四法简述于下。 1 由电力线来确定电力线的方向是电势降低的方向。顺着电力线,电势是逐点降低的,只要画出了电力线,那么电势的高低就可确定,这是最简便的方法。例1.如图1,空心金属球壳的球心处有一个带+Q电量的带电体,沿球壳半径方向空间里的A、B两点,它们的电势关系是: How to determine the potential of each point in the electrostatic field is a difficult point in teaching. After years of teaching practice, the author has summed up the following four simple and easy methods, that is, students in the middle and lower levels can also grasp, and hereby summarize the four methods. 1 The direction of the power line is determined by the power line. Along the power line, the potential is reduced point by point, as long as the power line is drawn, then the level of potential can be determined, which is the easiest method. Example 1. As shown in Fig.1, there is a charged body with +Q charge at the center of the hollow metal sphere shell, along the two points A and B in the radial direction of the sphere shell, their potential relationship is: