Question

Question 9 Horizontally polarized light is incident on the 5 polarizers below. Rank the intensity of the transmitted light from the polarizers from high to low. OO୦୦୦ A B C D E NOTE: We are interested in seeing how the light is transmitted from each polarizer independently. They are not used sequentially. The incident light has the same intensity in each case. Instructions: Use the drop-down menu to select the correct ranking from the right. If two have the same value, select the same rank for both. You do not need to use every rank (e.g. if they all had the same intensity, you would choose "Highest" for all five) Polarizer A 1. Highest Polarizer B 22nd Highest Polarizer C 3. 3rd Highest Polarizer D 4. 4th Highest Polarizer E 5. 5th Highest

Answer 1

According to Malu's law, the intensity of the polarized is proportional to cos²$\theta$, where $\theta$ is the polarization angle.
In the case of A, $\theta$ = 0, cos²(0) = 1, this gives highest intensity.
In the case of C, $\theta$ = 90, cos²(90) = 0, which gives the lowest intensity
Comparing B and D, the angle $\theta$ is smaller for B, so its intensity is greater
D and E gives the same intensity since one is rotated $\theta$ clockwise and the other anticlockwise (cos²(180 - $\theta$ ) = cos²$\theta$)

A - Highest
B - 2nd highest
D - 3rd highest
E - 3rd highest
C - 4th highest