把两个定值电阻R1、R2并联接入电压恒定的电路中,通过它们的电流分别为I1和I2.已知R1=nR2.并测出干路电流为I.试证明I1=1n+1I.答案:证明:并联电路电流与电阻成反比有I1I2=R2R1∵R1=nR2∴I2=nI1又∵I=I1+I2∴I=I1+nI1=I1(n+1)∴I1=1n+1I来源:天天语录网