Answer:
55.42°
Explanation:
According to malus law of intensity when an unpolarized light of intensity [tex]I_0[/tex] is passed through a two Polaroid sheets then the intensity becomes
[tex]I=\frac{I_0}{2}cos^2\Phi[/tex]
We have given the ratio [tex]\frac{I}{I_0}=0.161[/tex]
So [tex]0.161=\frac{1}{2}cos^2\Phi[/tex]
[tex]cos^2\Phi =0.322[/tex]
[tex]cos\Phi =0.5674[/tex]
[tex]\Phi =55.42^{\circ}[/tex]
