The intensity of an electromagnetic wave is $10\mathrm{W}/{\mathrm{m}}^2$. What will the intensity be if:

a. The amplitude of the electric field is doubled?

b. The amplitude of the magnetic field is doubled?

c. The amplitudes of both the electric and the magnetic fields are doubled?

d. The frequency is doubled?

The energy crossing per second per unit area parallel to the direction of propagation of electromagnetic waves is defined as the intensity of electromagnetic waves. where c is the electromagnetic wave's velocity.

The energy of such a wave is proportional of its amplitude (E2 or B2). This really is valid for waves on strings, water waves, and sound waves, where amplitude and pressure are proportional. The maximum field strength of the electric and magnetic is the amplitude in electromagnetic waves.

As a conclusion, the energy carried by such an electromagnetic wave and also its intensity $I$is proportional to $E2$and $B2$.In fact, the increasing quality wave of such a continuous oscillatory electromagnetic field is given by

$I_{\mathrm{ave}}=\frac{c{ϵ}_0{E}_0^2}{2}$