主要由滑动变阻器与负载接成的分压与限流电路(图1～2),是中学乃至大学电学实验中最常用的电路。通过改变变阻器R_o的触点位置,分压与限流电路均可起调节负载R_L上电压或电流大小的作用。虽然两种电路均可调节电压或电流的大小,但在不同的条件下,调节效果大不一样。现就此问题谈谈两种电路的特点及应用时的选择。 The voltage divider and current limiting circuit (Fig. 1~2) mainly composed of a sliding rheostat and a load is the most commonly used circuit in secondary and even university electrical experiments. By changing the contact position of the varistor R_o, the voltage divider and the current limiting circuit can all play a role in adjusting the magnitude of the voltage or current on the load R_L. Although both circuits can adjust the voltage or current size, the adjustment effect is quite different under different conditions. Now talk about the characteristics of the two circuits and the choice of application.