在力学中,我们经常使用功能关系解决问题,功能关系包括重力做功与重力势能变化的关系、弹力做功与弹性势能变化的关系以及合外力做功与动能变化的关系等。应用功能关系时,我们可以不考虑研究对象的具体运动过程和状态的变化,只考虑初、末位置的外力做功和研究对象的能量变化,是分析解决问题行之有效的方法,特别对于多过程的问题,用功能关系可以省去中间过程的复杂多 In mechanics, we often use functional relationships to solve problems. The functional relationships include the relationship between gravity work and gravity potential energy, the relationship between elastic work and elastic potential energy, and the relationship between external work and kinetic energy changes. When functional relationships are applied, we can not consider the specific movement process and state changes of the research object, and only consider the external forces of the initial and final positions and the energy changes of the research object. This is an effective method for analyzing and solving problems, especially for multiple processes. Problem, the use of functional relationships can save the complexity of the intermediate process