Question

An unpolarized beam of light with an intensity of 4000 W/m2 is incident on two ideal polarizing sheets. If the angle between the two polarizers is 0.429 rad, what is the emerging light intensity

Answer 1

The intensity is
`I_2 = 1654 \ W/m^2`

Step-by-step explanation:

From the question we are told that

The intensity of the unpolarized light is
`I_o = 4000 \ W/m^2`

The angle between the ideal polarizing sheet is
`\theta = 0.429 \ rad = 0.429 * 57.296 = 24.58^o`

Generally the intensity of light emerging from the first polarizer is mathematically represented as

`I_2 = (I_o)/(2)`

substituting values

`I_1 = (4000)/(2)`

`I_1 = 2000 \ W/m^2`

Then the intensity of incident light emerging from the second polarizer is mathematically represented by Malus law as

`I_2 = I_1 cos^2 (\theta )`

substituting values

`I_2 = 2000 * [cos (24.58)]^2`

`I_2 = 1654 \ W/m^2`