Please help Unpolarized light of intensity 320 Wcm2 is incid

Unpolarized light of intensity 32.0 W/cm^2 is incident on two polarizing filters. The axis of the first filter is at an angle of 28.0^degree counterclockwise from the vertical (viewed in the direction the light is traveling), and the axis of the second filter is at 61.0^degree counterclockwise from the vertical. What is the intensity of the light after it has passed through the second polarizer? W/cm^2

Solution

Intensity of unpolarized light is multiplied by 0.5 by the 1st polarizer. Subsequent polarizers multiply intensity by cos(theta)^2, where theta is the angle between previous and current polarizer.
Thus I = 32*0.5*cos(33d)^2 = 11.253 W/cm^2.