因为并联电路两端的电压相等,所以:
I1*R1=I2*R2=I*R并=I[R1*R2/(R1+R2)]=U
则 R1支路的电流为I1=U/R1或
I1=I[R1*R2/(R1+R2)]/R1=I*R2/(R1+R2)
又或:I1=I-U/R2