Hello I am trying to understand Malus' Law and the Intensity of light. Lets say I have three polarizers. The first polarizer and the last polarizer have the same axis of polarization. The middle polarizer can be rotated to an angle [tex]\theta[/tex] I know that Malus's Law for the intensity of light is I = I_0 cos^2 \theta for light coming out through the second polarizer. But how would I work out the intensity of light passing through the third filter. Should I multiply by [tex] cos^2 \theta[/tex] again, or should I treat the final two polarizers as just two polarizers?