e^(jωt) ; ω = 2πf
Z𝑊 = σ(1 − j) / √ω
Z = Rₛ + [jωCdl + (Rct + Z𝑊)⁻¹]⁻¹
V(t) = V̂ cos(ωt)
I(t) = V̂/|Z| cos[ωt − arg(Z)]
Nyquist: (Z′, −Z″) ; Bode: |Z|, arg(Z)