开关闭合、断开或滑动变阻器滑片移动都能使电路的总电阻发生变化,最终引起某段电路的电流或电压发生变化,这就是动态电路.解动态电路问题应明确: (1)电源电压恒定,测量电源电压的电压表示数不变; (2)电流表内阻很小,可视为导线;电压表内 Switch closure, disconnection or sliding varistor slider movement can make the total resistance of the circuit change, eventually causing a certain section of the circuit current or voltage changes, which is the dynamic circuit. Solution dynamic circuit problems should be clear: (1) power supply voltage Constant, measurement voltage of the power supply voltage is unchanged; (2) The internal resistance of the ammeter is very small and can be regarded as a wire; within the voltmeter