27) R1=2 Ом R2=8 Ом r=0.4 Ом E=10 B I=? I1=? I2=? U=?
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Ro=R1*R2/(R1+R2)=2*8/(2+8)=1.6 Ом
I=E/(Ro+r)=10/(1.6+0.4)=5 A
U=I*Ro=5*1.6=8 B
I1=U/R1=8/2=4 A
I2=U/R2=8/8=1 A
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29) I1*(R1+r)=I2*(R2+r)
r=(I2*R2-I1*R1)/(I1-I2)
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30) E=32 B r=0.25 Ом R1=5 Ом R2=15 Ом U=?
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Ro=R1*R2/(R1+R2)=5*15/(5+15)=3.75 Ом
I=E/(Ro+r)=32/(3.75+0.25)=8 A
U=I*Ro=8*3.75=30 B
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