# How does polarisation of EM wave work?

Does it removes either the electric wave of magnetic wave component of the EM wave?

And if so, won't the wave exiting the polariser not a EM wave anymore? More like an E wave or M wave.

If the above argument is correct, won't the speed of light become$$\frac{1}{\sqrt{\epsilon_{0}}}$$ or $$\frac{1}{\sqrt{\mu_{0}}}$$

jtbell
Mentor
No, an EM wave always has both electric and magnetic fields. The direction of polariztion refers to the direction of the electric field, by convention. A linear vertically polarized wave has the electric field oscillating up and down, and the magnetic field oscillating left and right. A linear horizontally polarized wave has the electric field oscillating left and right, and the electric field oscillating up and down.

Born2bwire