Question

Originally, light is unpolarized. It then travels through 3 polarizers: the first with its transmission axis aligned vertical, the next at a 30 degree angle to the vertical and the last aligned at a 45 degree angle to the vertical (tilted the same direction as the first with respect to the vertical). The original intensity of light is 4 W/m2. 3) What is the intensity of light after the first polarizer? A. 4 W/m2 B. 2 W/m2 C. 1.5 W/m2 D. 1.4 W/m2 E. 1.0 W/m2 F. 0 W/m2

Answer 1

C. 1.5 W/m²

Step-by-step explanation:

`I_0` = Unpolarized light = 4 W/m²

`\theta` = Angle with which the polarizer is turned

The polarization of light is given by

`I=(I_0)/(2)cos^2\theta\\\Rightarrow I=(4)/(2)cos^2(30)\\\Rightarrow I=2* \left((\sqrt3)/(2)\right)^2\\\Rightarrow I=1.5\ W/m^2`

The intensity of light after passing through the first polarizer is 1.5 W/m²