Question

Two polarizing sheets have their transmission axes crossed so that no light gets through. A third sheet is inserted between the first two such that its transmission axis makes an angle ? with that of the first sheet. Unpolarized light of intensity I₀ is incident on the first sheet. Find the intensity of the light transmitted through all three sheets for the following values of ?.

(a) ? = 12°
through first sheet
___ I₀
through first two sheets
___ I₀
through all three sheets
___ I₀

Answer 1

Through first sheet 0.5I₀

Through second sheet

$I_{2}=0.5I_{0}Cos^{2}\theta$

$I_{2}=0.5I_{0}Cos^{2}12$

$I_{2}=0.47838I_{0}$

Through all the three sheets

$I_{3}=I_{2}Cos^{2}(90-12)$

$I_{3}=0.020679I_{0}$