解答:解:设外电路总电阻为R,则:
=1 R
+1 R1
+1 R2
=1 R3
+1 8
+1 8
=1 4
①1 2
代入得外电路总电阻 R=2Ω ②
路端电压 U=
E=R R+r
×1.5V=1V2 2+1
则通过三个电阻的电流分别为
I1=
=U R1
A=0.25A,I2=I1=0.25A,I3=2 8
=U R3
A=0.5A,2 4
答:通过三个电阻R1,R2,R3上的电流分别为0.25A,0.25A和0.5A.