浮力是力学的重点,因而也是考试的热点.解浮力综合性问题一般要对物体所处状态作受力分析,再根据力的平衡条件列方程.但在这过程中未知量人为地增加,加大了解题难度.本文提出另一种思路,将物体所处的各个状态连成整体,从物体所受浮力变化情况着手,可简化问题. Buoyancy is the focus of mechanics, and thus is also a hot topic of the exam. The comprehensive problem of buoyancy liberation is generally based on force analysis of the state of the object, and then listed equations according to the equilibrium conditions of force. But in this process, the unknown quantity is artificially increased. To understand the difficulty of the problem, this paper proposes another way of thinking, which integrates the various states of the object, and simplifies the problem by starting from the change of buoyancy of the object.