Who produced electromagnetic waves for the first time?

$A$ plane electromagnetic wave of angular frequency $\omega$ propagates in a poorly conducting medium of conductivity $\sigma$ and relative permittivity $\varepsilon$. Find the ratio of conduction current density and displacement current density in the medium.

Maxwell's equations describe the fundamental laws of

$A$ parallel plate capacitor with circular plates of radius $R$ is being charged as shown. At the instant shown,the displacement current in the region between the plates enclosed between $\frac{R}{2}$ and $R$ is given by

To establish an instantaneous displacement current of $I$ ampere in the space between the plates of a parallel plate capacitor of $\frac{1}{2} \text{ F}$,the value of $\frac{dV}{dt}$ is .......

Inside a parallel plate capacitor,the electric field $E$ varies with time as $t^2$. The variation of the induced magnetic field with time is given by