How Does the Angle of Polarizing Sheets Affect Transmitted Light Intensity?

[phy112]

Homework Statement

Two sheets of polarizing material are placed with their transmission axes at right angles to each other. A third polarizing sheet is placed between them with its transmission axis at 46° to the axis of the first one.

(a) If unpolarized light of intensity I0 is incident on the system, what is the intensity of the transmitted light?
X Io

(b) What is the intensity of the transmitted light when the middle sheet is removed?
X Io

Homework Equations

I=.5Io
I=Iocos2theta

The Attempt at a Solution

I am confused on what they want! (the answers are in X Io

 

[phy112]

so i got b is zero(which is correct). is A the same?

 

[Redbelly98]

No, A is different.

Break it up into single steps. You already know what the first polarizer does to intensity. Each addition polarizer transmission depends on it's angle relative to the previous polarizer.

 

[phy112]

i tried every thing and i can't figure it out. is there any more hints

 

[Redbelly98]

Step 1:
What is the intensity after the 1st polarizer?