# Consider three polarizing disks whose planes are parallel and centered on the common axis. The...

## Question:

Consider three polarizing disks whose planes are parallel and centered on the common axis. The directions of their transmission axes relative to the vertical are respectively: {eq}\theta_1 {/eq} = 34 degrees clockwise, {eq}\theta_2 {/eq} = 24 degrees counter-clockwise and {eq}\theta_3 {/eq} = 17 degrees clockwise. A beam of light polarized along the vertical is incident onto the first polarizer with an intensity of {eq}\rm I_0 = 42 \ W/m^2 {/eq}. Calculate the transmitted intensity through all three polarizers.

## Polarization

The Law of Malus allows one to calculate the amount of light intensity which passes through a polarizer. It says that the fraction of the original light which passes through is proportional to the square of the cosine of the angle between the original polarized light and the polarizing filter.

{eq}\begin{equation*} I = I_o \, \cos^2{\theta} \end{equation*} {/eq}

If we have a system of multiple filters, we multiply each result to get the total.

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