Share
An unpolarized light with an intensity of 20W/m^2 is passed through a pair of polarizers. The first polarizer is set at an angle of 60° and
Question
An unpolarized light with an intensity of 20W/m^2 is passed through a pair of polarizers. The first polarizer is set at an angle of 60° and the second is set at an angle of 20°. Using Malus’ law, what is the intensity of light as it passes through the second polarizer?
in progress
0
Physics
3 years
2021-07-29T19:22:39+00:00
2021-07-29T19:22:39+00:00 1 Answers
6 views
0
Answers ( )
Answer:
4.416 W/m²
Explanation:
Malus’ law is given mathematically as
I = I₀ cos² θ
For the first polarizer, θ = 60°
I₁ = I₀ cos² 60°
I₁ = I₀ (0.5)² = 0.25I₀
For the second polarizer, θ = 20°
I₂ = I₁ cos² 20°
I₂ = I₁ (0.9397)² = 0.883 I₁
I₂ = 0.883 × 0.25I₀ = 0.2208 I₀
Note that
I₀ = 20 W/m²
I₂ = 0.2208 × 20 = 4.416 W/m²
Hope this Helps!!!