R1=10 R2=15 R3=4 R4=4 R5=15 R6=10 U=30 B U1=? Ro=?
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R12=R1*R2/(R1+R2)=10*15/(10+15)=6
R123=R12+R3=6+4=10
R1235=R123*R5/(R123+R5)=10*15/(10+15)=6
R12345=R1235+R4=6+4=10
Ro=R12345*R6/(R12345+R6)=10*10/(10+10)=5 Ом
Io=U/Ro=30/5=6 A
I6=U/R6=30/6=3 A
I1235=I4=Io-I6=6-3=3 A
U5=U-I1235*R4=30-3*4=18 B
I5=U5/R5=18/15=1.2 A
I3=I1235-I5=3-1.2=1.8 A
I12=I3
U1=U2=I3*R12=1.8*6=10.8 B
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