解得:
I1 |
I2 |
3 |
2 |
U1=I1(R1+RA),U2=I2(R1+RB)
解得:5R1+9RA=4RB-----------①
电源两端电压不变,I1(R1+RA+R2)=I2(R1+RB+R2)
解得:R1+3RA+R2=2RB--------------②
R1 |
R2 |
1 |
2 |
由①②③式得:RB=2R1------------------④
将④式代入①式解得:
RA |
RB |
1 |
6 |
(2)由甲图可得:
U1 |
U |
R1+RA |
R1+RA+R2 |
因R2=2R1,RB=2R1,RA=
1 |
6 |
1 |
3 |
答:(1)RA与RB的阻值之比为
1 |
6 |