动量守恒定律和机械能守恒定律是两个重要的定律,它们各自有成立条件和适用范围,既有区别也有联系,学生在研究具体物理问题时往往混淆。特别是近几年高考试题中经常有两守恒定律相关的综合题,即一道试题编织了对两守恒定律的理解、区分、正确应用诸方面知识、 The law of conservation of momentum and the law of conservation of mechanical energy are two important laws. They have their own conditions of establishment and scope of application. There are differences and connections. Students often confuse when they study specific physical problems. In particular, in recent years, high-test questions often have a comprehensive question related to two conservation laws, that is, a question woven to understand, distinguish, and correctly apply various aspects of the law of two conservations.