Unpolarized light is passed through polarizer 1. The light then goes though polarizer 2 with its plane of polarization at 40.7° to that of polarizer 1. Polarizer 3 is placed after polarizer 2. Polarizer 3 has its plane of polarization at 54.8° to the plane of polarization of polarizer 2 and at 95.5° to that of polarizer 1. What fraction of the intensity of the original light gets though the last polarizer?

The fraction of the intensity of the original light that got through the last polarizer is  

Explanation:

   From the question we are told that  

       The angle between polarizer 2  and polarizer 1 is  

       The angle between polarizer 3 and polarizer 2 is  

        The angle between polarizer 3 and polarizer 1 is

The intensity of light emerging from the first polarizer can be obtained using the one half rule as follows

Here is the intensity of light emerging from the polarizer 1

          is the intensity of the unpolarized light

The intensity of light emerging from the second polarizer is obtained using the cosine-squared rule the intensity of light incidenting on the second polarizer is already polarized by the polarizer 1

    So the intensity is mathematically represented as

  substituting for

Substituting values

The intensity  emerging from polarizer 3 is obtained using the cosine-squared rule as follows

substituting for

the answer is a. hope this .