Snell's Law

Refraction angle and critical angle with a ray diagram

1 · sin(θ₁) = 1.5 · sin(θ₂)

Refraction angle (θ₂)

19.47°

Critical angle (θc)

None (n₁ ≤ n₂)

Light bends toward the normal when entering a denser medium (n₂ > n₁) and away from it when entering a rarer one. Snell's law relates the angles: n₁·sin(θ₁) = n₂·sin(θ₂).