r1=3欧,r2=4欧并联接入电路,则u1比u2=?i1比i2?i1比i?i2比i

题目

r1=3欧,r2=4欧并联接入电路,则u1比u2=?i1比i2?i1比i?i2比i

答案

并联电路每条支路的电压相等,所以U1/U2=1
I1/I2=(U/R1)/(U/R2)=R2/R1
R总=(R1R2)/(R1+R2)
I1/I=(U/R1)/(U/R总)=(U/R1)/U(R1+R2)/(R1R2)=R2/(R1+R2)
同理 I2/I=R1/(R1+R2)