The refractive index (n) of a medium is inversely proportional to the speed of light (v) in that medium, according to the formula n = c/v, where c is the speed of light in a vacuum. Therefore, v = c/ n. A higher refractive index means a lower speed of light, and a lower refractive index means a higher speed of light.
The refractive index of fused quartz is 1.46 and that of sapphire is 1.77. If vq is the speed of light in quartz and vs is the speed of light in sapphire, then which one of the following relations is correct ?
Asked in UPSC NDA 2 2020 · Topic: Optics (Reflection and Refraction at plane and spherical surfaces)
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