When a ray of light travels from a denser medium (like glass or water) to a rarer medium (like air), its speed increases. According to Snell's Law and the principle of least time, the ray bends away from the normal drawn at the point of incidence.
When a ray of light travels from a denser medium to a rarer medium then
Asked in CGPSC Prelims Exam 2018 · Topic: Optics (Reflection and Refraction at plane and spherical surfaces)
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