Question

1个电阻与1个3欧的电阻串联后接在原电路中,发现通过的电流变为原来的5分之4,则此电阻的阻值是?

Answer 1

U/R=Io

U/(R+3)=(4/5)Io

两式相此

(U/R)/[U/(R+3)]=[Io/(4Io/5)]

R/(R+3)=4/5

此电阻的阻值为

R=12欧