1.
R = 20 Ω
t = 2 min = 120s
Q = 220 C
e = 1,6*10⁻¹⁹ C
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I, U, n
Q = I*t
I = Q/t = 220C/120s = 1,8(3) A ≈ 1,83 A
I = 1,83 A
U = I*R = 1,83A*20 Ω = 36,6 V
U = 36,6 V
Q = n*e
n=Q/e = 220C/ 1,6*10⁻¹⁹C = 220/1,6 * 10¹⁹ =137,5 * 10¹⁹ elektronów
n = 137,5 * 10¹⁹ elektronów
2.
P =1 kW = 1000 W
U = 120 V
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I, R ?
P = U*I
I = P/U = 1000W/120V = 8,33 A
I = 8,33 A
R = U/I = 120V/8,33A = 14,4 Ω
R = 14,4 Ω
3.
R = 10 Ω
L2 = 10L
S2 = S/5
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R2 ?
R = ρL/S
R2 = ρL2/S2 = (ρ*10L)/(S/5) = 50 * ρL/S = 50 * R = 50*10Ω = 500 Ω
R = 500 Ω
