电阻R1=15Ω、R2=10Ω，R1、R2串联后的总电阻是Ω；并联后的总电阻是Ω．

Question

电阻R₁=15Ω、R₂=10Ω，R₁、R₂串联后的总电阻是______Ω；并联后的总电阻是______Ω．

Answer 1

R₁、R₂串联后的总电阻是R=R₁+R₂=15Ω+10Ω=25Ω；
R₁、R₂并联后的总电阻为(1)/(R′)=(1)/(R1)+(1)/(R2)
R′=(R1R2)/(R1+R2)=(15Ω×10Ω)/(15Ω+10Ω)=6Ω．
故答案为：25；6．