Calculate the refractive index or the speed of light in a medium.
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Quick Reference
nRefractive Index
c299,792,458 m/s
vVelocity in Medium
Overview
The refractive index (n) of a material is a dimensionless number that describes how fast light travels through that material compared to a vacuum. It is defined as n = c/v.
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Pro Tips
The index of refraction is always greater than or equal to 1.0.
A higher index of refraction means light travels slower in that medium.
The change in speed causes light to bend when entering a new medium (refraction).
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Fun Facts
"Diamond has one of the highest refractive indices of any natural clear substance, giving it its famous brilliance."
"Light travels about 25% slower in water than in a vacuum."
"The refractive index of air changes slightly with temperature and pressure, which causes mirages."
