A source emits a beam of light with a wavelength of 525 nm and an intensity of 500 W/m, the beam is incident on a system

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A source emits a beam of light with a wavelength of 525 nm and
an intensity of 500 W/m, the beam is incident on a system of three
polarizers where the second and third polarizer form angles of 30
and 450 respectively with respect to the first polarizer. The beam
then passes through an opening with a width of 0.2 mm forming a
pattern of interference on a screen located at a distance of 1.2 m.
Determine:
a) The intensity of the beam after passing through the polarizer
system.
b) The angle and height with which the first minimum is formed
on the screen.
c) The numerical value of the relationship between the intensity
at the 1.5 mm point with respect to to the intensity of the
original source.
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