Question

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Varianta 16​

Answer 1

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