解力学平衡问题,是对物体进行受力分析并选择适当的坐标系,列出联立方程再进行运算得出解答.这样处理要用到许多数学知识,方程求解中有可能出现多解,物理意义很难理解.而平衡问题与“三角形”有关,能灵活运用力的封闭“三角形”性质,特别是在解决物体受三个力作用下的动态平衡的问题,可化难为易,简捷直观.本文将从四个方面介绍“三角形”的性质在处理平衡问题中的应用. The problem of solution mechanics balance is the force analysis of the object and the selection of the appropriate coordinate system. The simultaneous equations are listed and the operation is carried out to solve the problem. This process requires the use of many mathematical knowledge. There may be multiple solutions in the solution of the equation. The meaning is difficult to understand. The balance problem is related to the “triangle” and can be used flexibly to close the “triangle” nature, especially in solving the problem of the dynamic balance of an object under the action of three forces. It can be difficult to change, simple and intuitive. This article will introduce the application of “triangle” in the balance of the problem from four aspects.