Displacement current $\left(i_d\right)=\frac{\varepsilon_o d \phi_E}{d t}$.
Where symbols have their usual meanings.
Which of the following options gives correct equation for displacement current?
Answer & explanation
Correct answer: option 2
$ i_d = \epsilon_0 \frac{d\phi_E}{dt} = \epsilon_0 \frac{d(EA)}{dt} = \epsilon_0 A\frac{dE}{dt}$