1) i = Q/t
5= 1/1/5
E
2) i=12/60
i = 0,2 A
3) i = n x e/t
8 = n x 1,6 x 10^-19/5
n = 40/1,6 x 10^-19
n = 25 x 10^19
4) i = 2 x 10^18 x 1,6 x 10^-19/1
i = 3,2 x 10^-1
i= 0,32 A
B
5) U = R x i
20 = R x 4
R = 5 Ω
U’ = 5 x 3
U = 15 V
6) 40 = R x 4
R = 10 Ω
Semelhança de triângulos:
4/i2 = 40/100
i2= 10 A
7) 1,5 = R x 6
R = 0,25 = 2,5 x 10²
C
8) i = Q/t
i = 3 + 3/1
i = 6 A
E
9)a) R = ρ x L/A
R = 2,65 x 10^-8 x 10^6/5,26 x 10^-3
R = 5 Ω
b) P = i x U
10^8 = i x 10^5
i = 1000 A
10) U = R x i
112 = R x 0,5
R = 56 Ω
56 = ρ x L/π
R’ = ρ x L/4π
R’ = 56/4
R’ = 14 Ω