If $\epsilon, E$ and $t$ represent the free space permittivity, electric field and time respectively

Question

If $\epsilon, E$ and $t$ represent the free space permittivity, electric field and time respectively, then the unit of $\frac{\epsilon E}{t}$ will be :

Professor PC Thomas Classes · Answer

According to Maxwell's equations, the term $\epsilon_0 \frac{dE}{dt}$ represents the displacement current density ($J_d$). Since current density is defined as current per unit area, its SI unit is $	ext{Ampere}/	ext{meter}^2$ ($\mathrm{A} / \mathrm{m}^2$). Therefore, the unit of $\frac{\epsilon E}{t}$ is $\mathrm{A} / \mathrm{m}^2$.