R1=500Ом, R1=R2=R3=R4, U=12В, R основной=?

Question

R1=500Ом,
R1=R2=R3=R4,
U=12В,
R основной=?

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Answer 1

R14=R/2=500/2=250 Ом
R23=R+R=500+500=1000 Ом
Ro=R14*R23/(R14+R23)=250*1000/(250+1000)=200 Ом
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