Question

Question 10 (4 points) Malus's Law Below is an image of light with initial intensity lo = 750.0 W/m2 going through 2 polarizing filters. The first polarizing filter is oriented with vertical polarization. The angle between the two polarizing filters is = 48.0 degrees. The light is initially polarized horizontal before entering the first polarizing filter. What is the intensity of the light at 12 (after passing through both filters)? Make sure to give your answer in units of W/m2 and with an appropriate number of significant figures. Polarizing Filter Polarizing Filter 10 11 12 Your Answer: Answer

Answer 1

When polarised light passes through a polarizer, final intensity is given by:

I=Io*(cos k)^2, where I is final intensity, Io is initial intensity and k is the angle between polarizing axis and polarized light.

When light passes through first polarizer, Io=750 W/m2 and k=90 degrees because incident light is horizontally polarized while polarizing axis for the first polarizer is vertical .

So, after passing through first polarizer, intensity of light= 750*(cos90)^2= 0 W/m2.

So, final intensity of light passing through second polarizer is also 0 W/m2.