The voltage across an impedance in a network is $V(s)=z(s) I(s)$, where $V(s)$, $Z(s)$ are the Laplace transforms of the corresponding time function $v(t), z(t)$ and $i(t)$. The voltage $v(t)$ is:
- $v(t)=z(t) \cdot v(t)$
- $v(t)=\int_0^1 i(t) \cdot z(t-\tau) d \tau$
- $v(t)=\int_0^1 i(t) \cdot z(t+\tau) d \tau$
- $v(t)=z(t)+i(t)$