Engineering Physics: Unit II: Electromagnetic Waves

Conditions on the Wave Field

If the plane polarized waves is propagating along x-axis having electric vector along the y-axis, we have

CONDITIONS ON THE WAVE FIELD

If the plane polarized waves is propagating along x-axis having electric vector along the y-axis, we have

Ey ≠ 0, Ez = Ex = 0 and 

Similarly for magnetic field vector

Hz ≠ 0, Hy = Hx = 0

Therefore, the wave equations for plane electromagnetic wave reduce to


since at the given value of x, Ey and Hz are constant at any instant. Further and are varying only in x-direction which is the direction of propagation of these fields as shown in fig. 2.4.



Substituting eqn (7) in eqn (3) and eqn (8) in eqn (4) we have


Solutions of the plane Wave Equations 

The plane wave equations for electric field and magnetic field are given by


c- speed of EM wave

The solutions of the above wave equations of progressive wave are given by


where, ω - angular frequency

k - wave vector

Here E0 and H0 are the maximum values (amplitudes) of the electric and magnetic vectors respectively.

The general solution of the wave equation is written as


where c is the wave velocity. 



Engineering Physics: Unit II: Electromagnetic Waves : Tag: : - Conditions on the Wave Field