V

Ω
Ω
Ω

V = I × R  ·  I = V / R  ·  R = V / I
R = R₁ + R₂ + R₃
1/R = 1/R₁ + 1/R₂ + 1/R₃
P = V × I = I² × R = V² / R
H = I² × R × t
E = P × t  ·  1 kWh = 3.6 × 10⁶ J