有一些物理问题,用直接方法解答是相当繁琐的,或者用中学所学知识直接求解是无从下手的。若用割补法,常可将研究对象及有关的图形、图线,通过合理、恰当的假设,宏观的分割或填补,使非对称形体变为对称形体,使隐含条件和关系充分显 There are some physical problems, the direct method is very complicated to answer, or solve directly with the knowledge of secondary school is impossible to start. If the cut-off method is used, the object of study and the related graphs and diagrams can often be transformed into symmetrical forms through rational and appropriate assumptions, macroscopic segmentation or filling, so that the implied conditions and relations are fully manifested