Question

Номер 4 и 5
Помогите плизз

Answer 1

4) U=220 B   t=4*60=240 c   Q=14400 Дж   R=?
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Q=U²*t/R
R=U²*t/Q=220²*240/14400≈806 Ом
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5) U3=15 B
R12=R1*R2/(R1+R2)=6*3/(6+3)=2 Ом
I=U3/R3=15/5=3 A
U1=U2=I*R12=3*2=6 B
P2=U2²/R2=36/3=12 Вт
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