A physical quantity 'P' is given by $P=\epsilon_0 L \frac{\Delta V}{\Delta t}$, where $\epsilon_0$ is electric permittivity, $L$ is length, $\Delta \mathrm{V}$ is potential difference and $\Delta \mathrm{t}$ is time interval. The dimensional formula of $\mathrm{P}$ is same as that of