在如图所示电路中,电源电压为6V,电阻R1的阻值是20Ω,开关闭合后,通过电阻R2的电流为0.6A.求:(1)

2025-05-09 14:46:47
推荐回答(1个)
回答1:

(1)∵R1、R2并联,
∴通过电阻R1的电流:
I1=

U1
R1
=
U
R1
=
6V
20Ω
=0.3A;
(2)干路电流:
I=I1+I2=0.3A+0.6A=0.9A,
R1和R2的总电阻:
R=
U
I
=
6V
0.9A
≈6.7Ω;
(3)电阻R1消耗的电功率:
P1=UI1=6V×0.3A=1.8W.
答:(1)通过电阻R1的电流是0.3A;
(2)R1和R2的总电阻约为6.7Ω;
(3)电阻R1消耗的电功率是1.8W.