Question

Unpolarized light is incident on a waveguide made of a dense glass (index of refraction n₂ ) that is coated with a layer of quartz (index of refraction n₃). The waveguide is immersed in a medium with index of refraction n_1.

Assume the wavelength of of the incident light is 500 nm, n₁ = 1.00, n₂= 1.80 and n₃ = 1.45.

A) The speed of light in the dense glass is most nearly                            [ Select ]                       ["1.50", "3.00", "2.00", "1.875", "1.67", "2.25"]         x 10⁸ m/s

B) The critical angle for total internal reflection off the dense glass / quartz surface is                            [ Select ]                       ["47.3", "56.3", "63.3", "53.7", "69.0"]      

C) For the beam reflecting off the air/dense glass surface to be completely polarized, θ 1 would have to be                            [ Select ]                       ["63.4", "56.3", "58.0", "47.3", "60.9"]      

D) If the beam reflecting off the air/dense glass surface is completely polarized, the polarization would be                            [ Select ]                       ["perpendicular to the surface", "parallel to the surface", "Both parallel and perpendicular to the surface"]      

E) If the angle of incidence  θ 1 = 40 degrees, θ 2=                            [ Select ]                       ["22.5", "28.6", "13.2", "20.9", "25.4"]           and θ 3 =                            [ Select ]                       ["67.5", "90", "69.1", "64.6", "61.4"]      

F) Will the light totally internally reflect and stay in the dense glass or refract into the quartz?                            [ Select ]                       ["It will both reflect and refract", "It will totally reflect", "It will only refract", ""]      

Answer 1

Solution:

, ,

A)  

let the speed of light be v in dense glass.

  

  

B) 53.67

let the critical àngle be .

  

  

C) 60.95

For complete polarizatiotion,by Brewster's law

  

D) parallel to the surface.