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Varianta 16
![Varianta 16 class=](https://ro-static.z-dn.net/files/deb/03ee386d98aaabffd285584234355c70.jpg)
a) R12 =?
R12 = R1*R2/R1+R2 (deoarece aceste rezistente sunt in paralele)
R12 = 12 Ω
b) I = ?
U = I * Re ; Re = R12 + R3 = 20 Ω
=> I = U/Re = 50/20 => I = 2.5 A
C)Uab =?
Uab = I * R12 = 2.5*12 = 30 V