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DataGG
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Homework Statement
Write an expression for a light wave circular polarized to the right, traveling in the positive ZZ direction, such that the electric field points in the negative XX direction at z=0, t=0.
Homework Equations
Right handed polarization is the same as clockwise, I think..
##E_{0x} = E_{0y}## throughout the whole thing.
$$\vec{E}(z,t)=E_{0x}sin(kz - wt)\vec{i} + E_{0y}sin(kz - wt + \frac{\pi}{2})\vec{j}$$
The Attempt at a Solution
Well, I'm having a problem.
$$\vec{E}(z,t)=E_{0x}cos(kz - wt)\vec{i} + E_{0y}sin(kz - wt)\vec{j}$$
At ##z=0##, we have
$$\vec{E}(0,t)=E_{0x}cos(wt)\vec{i} - E_{0y}sin(wt)\vec{j}$$
So it indeed moves clockwise (co-sine decreases while the sin increases negatively)
At ##z=0## and ##t=0##:
$$\vec{E}(0,0)=E_{0x}\vec{i}$$ Which does not point in the negative XX direction.
If I place a minus in the co-sine term, then it'll look like this:
$$\vec{E}(0,t)= - E_{0x}cos(wt)\vec{i} - E_{0y}sin(wt)\vec{j}$$
and that means that the co-sine will decrease negatively and the sin increase negatively. That would be a left handed circular polarization, because it would be counter-clockwise. I think?
So, how do I go about doing this?
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