静电场是电学的核心知识之一,在物理学中占有非常重要的地位,也是高考命题的重点和热点。近几年来的高考物理试题中,频频出现以电场中电势(或电场强度)随距离变化的图象为信息,来考查电场中的力学与能量问题。这类试题由于未告之场源电荷,很多学生普遍觉得过于抽象,信息难以提取,解题便进入僵局。但对于这类图象问题,若能根据电势分布(或场强分布)情况建立具体的电荷模型,明确空间的电场分布,问题便迎刃而解了。 Electrostatic field is one of the core electrical knowledge, occupies a very important position in physics, but also the focus of college entrance examination proposition and hot spots. In recent years, college entrance examination physics questions, frequently appear in the electric field (or electric field strength) with the distance changes in the image as information to examine the electric field in the mechanics and energy issues. Due to the unpublished field source charge of such questions, many students generally feel too abstract, the information is difficult to extract, the problem will enter a deadlock. However, for such image problems, the problem can be easily solved if a specific charge model can be established according to the distribution of potential (or field strength distribution) and the electric field distribution of the space is clarified.