Question

在如图所示的电路中,R1=10欧,R2=20欧,闭合开关后,电流表的示数为0.6A。

(1)电阻R1两端的电压;(2)通过电阻R2的电流;(3)电路消耗的总功率

Answer 1

U=I1×R1=0.6A×10欧=6V

I2=U/R2=6V/20欧=0.3A

P1=UI=6V×0.6A=3.6W
P2=UI=6V×0.3A=1.8W
P总=P1+P2=3.6W+1.8W=5.4W

Answer 2

U=I1×R1=0.6×10=6
I2=U/R2=6/20=0.3A

总功率=P1+P2=6×0.6+6×0.3
=3.6+1.8
=5.4