1) R=po*L/S L=R*S/po=10*0.8/0.017=470 м
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2) R12=R1*R2/(R1+R2)=200*150/(200+150)≈85.7 Ом
Rобщ=R12*R3/(R12+R3)=85.7*180/(85.7+180)≈58 Ом
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3) I1=24 A t=180 c
U=I1*R1=24*6=144 B общее напряжение
I3=U/(R2+R3)=144/(2+6)=18 A
Q=I3²*R*t=18²*6*180=349920 Дж
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