一、知识结构二、知识要点（一）电流、电压与电阻的关系1．在电阻一定的情况下，电流跟电压成正比注意：（）保持电阻不变，研究电流跟电压的关系的电路图如图1所示，见课本P96图8一回．调节滑动变阻器的滑片，使R两端的电压成整数倍地增加；读出每次加在R上的电压值和通过R的 First, the knowledge structure Second, knowledge points (a) the relationship between current, voltage and resistance 1. In the case of a certain resistance, the current is proportional to the voltage Note: () to maintain the same resistance, the circuit diagram to study the relationship between current and voltage shown in Figure 1, see textbook P96 Figure 8 a back. Adjust the slide of the sliding rheostat so that the voltage across R increases by an integer multiple; read out the voltage value applied to R each time and pass through R