posted by Melissa .
The angle between the polarizer transmission axis and the plane of polarization of the incoming light is 30 +/- 2 deg. If the incident light intensity Io is 100 W/cm2 what would be the intensity I after the light is transmitted through the polarizer? What would be the percent error in intensity?
I = 100 cos30 = 86.6
Max = 100 cos28 = 88.3
Min = 100 cos32 = 84.8
Percent error: +/- 2%
This assumes a lossless polarizer (when aligned in the proper plane), such as a Wollaston or Nicol prism type. Polaroid sheet film has large losses, even in the plane of polarization.
It also assumes that the incoming radiation is perfectly plane-polarized.