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Formula Snell's Law Refractive index of the 1st medium    Angle of incidence    Angle of refraction

Formula
Formula: Snell's Law
Light Beam with Angle of Incidence and Refraction for Snell's Law

Refractive index of the 1st medium

Unit
Refractive index of one of the two media in which the light beam propagates. In vacuum, \( n_1 = 1 \).

Refractive index of the 2nd medium

Unit
Refractive index of the second medium into which the light beam is refracted.

Angle of incidence

Unit
Angle of incidence from the incident beam in the first medium. Measured relative to the normal (a line perpendicular to the surface).

Angle of refraction

Unit
Angle of refraction of the incident beam in the second medium. Measured relative to the normal.