All GRE Subject Test: Physics Resources
Example Question #7 : Electromagnetics, Waves, And Optics
A beam of unpolarized light passes through two linear polarizers whose polarization axes are at an angle theta with each other. The light initially has an intensity , and has an intensity of after passing through both polarizes. Find ?
Initially unpolarized light passing though a linear polarizer decreases in intensity by a factor of two:
Malus's Law gives the change in intensity of polarized light passing through a linear polarizer in terms of the change in angle of polarization:
Combining the two equations, we get:
Solving for :