一、控制变量法:当研究的一个物理量与2个或2个以上的其它物理量有关时,常采用只改变一个物理量,而控制其余物理量保持不变,从而得出被研究物理量和改变量的关系。这种方法是中学物理教学中最常用的方法之一。例如在研究导体中的电流跟哪些因素有关时,就是分别保持电压不变研究电流与电阻的关系,控制电阻不变研究电流与电压的关系。研究液体蒸发的快慢跟哪些因素有 First, the control variable method: When a study of a physical quantity and 2 or more other physical quantities, often only use one physical quantity, and control the rest of the physical quantity remains unchanged, so that the relationship between the physical quantity and the amount of change is studied. . This method is one of the most commonly used methods in middle school physics teaching. For example, when studying the current in a conductor, it is the relationship between the current and the resistance that holds the voltage constant, and the relationship between the current and the voltage is studied by controlling the resistance. Study how fast the liquid evaporates and what factors