exercice 1 :
1)puissance
exercice 2:
1 ) U=W/I 70/2 = 35.0V
2)V = A x Ω Ω = V/A = 35.0/2 = 17.5 Ω.
exercice 3
1) W = puissance V= tensions
2) I= W/V 1100/220 = 5.0 A
3) Ω = V/A =220/5 44.0
