Snell’s law: Quick Facts

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$Diagram illustrating Snell's law, showing light rays entering from a medium with refractive index n1 into a medium with refractive index n2, bending at the interface. Angles of incidence and refraction are labeled, with wavefronts and normal lines depicted to explain the change in direction due to differing refractive indices.$

$law of refraction$

$Snell's law diagram showing an incident ray striking the boundary between media n1 and n2, reflecting at equal angle theta 1 and refracting toward the normal at angle theta 2.$

$How does refraction affect light and vision?$

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refraction double refraction rainbow mirage refractive index Halo atmospheric refraction What causes mirages?Why are rainbows curved?

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Willebrord Snell

Dutch astronomer and mathematician