Bonjour,
1) P = P₁ + P₂ + P₃ = 70 + 30 + 20 = 120 W
2) P = U(MN) x I₁
⇒ I₁ = P/U(MN) = 120/12 = 10 A
3) U(MA) = P₁/I₁ = 70/10 = 7 V
Et U(AN) = U(MN) - U(MA) = 12 - 7 = 5 V
4) I₂ = P₂/U(AN) = 30/5 = 6 A
et I₃ = P₃/U(AN) = 20/5 = 4 A
On vérifie bien que : I₂ + I₃ = 6 + 4 = 10 A = I₁
