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Suppose that white light strikes a flat piece of flint glass in air, coming in at an angle of 60 degrees to the surface (30 degrees from the normal or perpendicular). The index of refraction of this dense glass for red light is 1.710, for green light is 1.723, and for blue light is 1.735. What is the order of colors you would see in the refracted light inside the glass as they leave the surface

User Rasputino
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Answer:

The order of the light starting from the light closest to the normal line is

Blue light, followed by green ight and then lastly red light

Step-by-step explanation:

White light travels from one medium to another such as from air to glass is refracted according to Snell's law as follows

n₁·sin(θ₁) = n₂·sin(θ₂)

The given parameters of the white light are;

The angle the incident (incoming) light makes with the surface = 90°

The angle of incidence of the light, θ₁ = 30°

The index of refraction of red light for the glass, n₂ = 1.710

The index of refraction of green light for the glass, n₃ = 1.723

The index of reaction of blue light for the glass, n₄ = 1.735

The refractive index of air, n₁ = 1

The angle of refraction of the red light, θ₂ is given as follows;

1 × sin(30°) = 1.710 × sin(θ₂)

sin(θ₂) = 1 × sin(30°)/1.710

θ₂ = sin⁻¹(1 × sin(30°)/1.710) ≈ 17°

The angle of refraction (to the surface's normal line) of the red light, θ₂ ≈ 17°

The angle of refraction of the green light, θ₃ is given as follows;

1 × sin(30°) = 1.723 × sin(θ₃)

sin(θ₃) = 1 × sin(30°)/1.723

θ₃ = sin⁻¹(1 × sin(30°)/1.723) ≈ 16.869°

The angle of refraction of the green light, θ₃ ≈ 16.869°

The angle of refraction of the green light, θ₄ is given as follows;

1 × sin(30°) = 1.723 × sin(θ₄)

sin(θ₄) = 1 × sin(30°)/1.735

θ₄ = sin⁻¹(1 × sin(30°)/1.735) ≈ 16.749°

The angle of refraction of the green light, θ₄ ≈ 16.749°

The order of colors we see as the in the refracted light inside the glass as the light leave the surface are;

The red light, with an angle of refraction of approximately 17° will be furthest from the normal

The green light which has an angle of refraction of 16.869° will follow and will be intermediate between the red and the blue light

The blue light which has an angle of refraction of 16.749° will follow next and it will be closest to the normal

The order of the light from the normal line will be blue, followed by green and then red light

User Malkocoglu
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