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Multiple Choice
Suppose a ray of light starts in air, then enters a slab of diamond with parallel faces, and then exits again. If the ray entered the diamond at an angle from a line normal to the diamond slab, what is true of the final angle from normal ?
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There is not enough information to answer this question.
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Verified step by step guidance
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Identify the principle of refraction involved: Snell's Law, which states that n1 * sin(θ1) = n2 * sin(θ2), where n1 and n2 are the refractive indices of the two media, and θ1 and θ2 are the angles of incidence and refraction, respectively.
Recognize that the problem involves a ray of light entering and exiting a slab with parallel faces. This means the light will undergo refraction twice: once when entering the diamond and once when exiting.
Apply Snell's Law at the first interface (air to diamond): n_air * sin(θi) = n_diamond * sin(θr), where θi is the angle of incidence and θr is the angle of refraction inside the diamond.
Apply Snell's Law at the second interface (diamond to air): n_diamond * sin(θr) = n_air * sin(θf), where θf is the angle of refraction as the light exits the diamond.
Since the slab has parallel faces, the angle of incidence θi is equal to the angle of refraction θf when the light exits the slab. Therefore, θf = θi, meaning the final angle from normal is equal to the initial angle from normal.