5) R246=R2+R4+R6=2+4+1.5=7.5
R2456=R243*R5/(R246+R5)=7.5*2/(7.5+2)=1.58
Ro=R1+R2456+R3=3.5+1.58+4=9
I=I1=I3=E/(Ro+r)=10/(9+1)=1 A
U2456=I*R2456=1*1.58=1.58 B
I5=U2456/R5=1.58/2=0.8 A
I2=I6=I4=I-I5=1-0.8=0.2 A
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6) m1=0.8 c1=880 c2=4200 m2=2 т=600 с
I²*R*т=0,85*Δt*(c1*m1+c2*m2)
Δt=I²*R*т/(0.85*(c1*m1+c2*m2))=4.5²*50*600/(0.85*(880*0.8+4200*2))≈78.5°C
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