Critical angle:
- The critical angle is the incidence angle at which the angle of refraction is .
- The light should flow from a denser optical medium towards a less dense optical medium.
- The critical angle will be for water-air boundaries and for crown glass-water boundaries.
Mathematical representation:
Refractive index:
A number determined by dividing the speed of light within a vacuum by the speed of light inside a denser medium is called the refractive index.
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