Who first produced electromagnetic waves?

What is the phase difference between the space current and the capacitive displacement current produced when radio waves pass through the ionosphere?

An accelerated electron produces ...

An electromagnetic wave of frequency $100 \text{ MHz}$ propagates through a medium of conductivity $\sigma = 10 \text{ mho/m}$. The ratio of maximum conducting current density to maximum displacement current density is . . . . . . . $\left[ \text{Take } \frac{1}{4 \pi \epsilon_0} = 9 \times 10^9 \text{ Nm}^2/\text{C}^2 \right]$

According to Maxwell,which is the missing term in Maxwell-Ampere circuital law?

$A$ parallel plate capacitor (Figure) made of circular plates each of radius $R=6.0\; cm$ has a capacitance $C=100\; pF$. The capacitor is connected to a $230\; V$ ac supply with a (angular) frequency of $300 \;rad \;s ^{-1}$.
$(a)$ What is the rms value of the conduction current?
$(b)$ Is the conduction current equal to the displacement current?
$(c)$ Determine the amplitude of $B$ at a point $3.0\; cm$ from the axis between the plates.