Understanding Polarization at Different Phases?

[Srv C]

Describe the state of polarization represented by
(here w = omega and TT = pi)

a) Ex = Esin(kz - wt) & Ey = Ecos(kz - wt)

b) Ex = Ecos(kz - wt) & Ey = Ecos(kz - wt + TT/4)

c) Ex = Esin(kz - wt) & Ey = Esin(kz - wt)

 

[BvU]

Hi C, and welcome to PF.

How did you get past the template ? It has a purpose (see guidelines).
So try providing a little more, please.
Good luck!