试用戴维南定理求图示电路中2Ω电阻的电流I_物理解答

试用戴维南定理求图示电路中2Ω电阻的电流I

人气：392 ℃　时间：2019-08-19 11:34:43

解答

先将电流源转换成电压源模式：

Us = 5 * 5 = 25 V
R = 5 + 10 = 15 Ω
I1 = (25 - 10) / (15+3) = 5/6 A
Uab = 20 + 3 * 5/6 = 22.5 V
Rab = 15 *3 /(15+3) = 2.5 Ω ；电压源短路,电阻并联.
I = Uab / (Rab + 2) = 22.5 / 4.5 = 5 A