Shortcut Methods
7 : Snell’s Law Shortcut for Plane Surfaces
When light passes from one medium to another through a plane surface (e.g., air to glass), Snell’s Law simplifies to: $$(n_1\sin(\theta_1) = n_2\sin(\theta_2)),$$ where n1 and n2 are the refractive indices, and θ1 and θ2 are the angles of incidence and refraction, respectively.