(1)在串联电路中,R总=R1+R2=4Ω+12Ω=16Ω
(2)在串联电路中,I1=I2.
I1=Ui/R1=12V/4Ω=3A,则I1=I2=3A.
由I=U/R,得U2=I2R2=3A×12Ω=36V.
(3)在串联电路中,U电源=U1+U2
则U电源=U1+U2=12V+36V=48V
(1)在串联电路中,R总=R1+R2=4Ω+12Ω=16Ω
(2)在串联电路中,I1=I2.
I1=Ui/R1=12V/4Ω=3A,则I1=I2=3A.
由I=U/R,得U2=I2R2=3A×12Ω=36V.
(3)在串联电路中,U电源=U1+U2
则U电源=U1+U2=12V+36V=48V