{\displaystyle {\begin{aligned}I(\omega )&=j\omega Q(\omega )=j\omega \oint _{\mathbb {S} }\mathbf {D} (\mathbf {r} ,\omega )\cdot \mathrm {d} \mathbf {a} \\&=\left[G(\omega )+j\omega C(\omega )\right]V(\omega )={\frac {V(\omega )}{Z(\omega )}}\\\end{aligned}}}