Refraction from glass (n = 1.5) into air at 30°

Answer: angle of refraction θ₂ = 48.59° (critical angle 41.81°).

What we know

Refractive index n₁ (incident): 1.5
Angle of incidence θ₁: 30°
Refractive index n₂ (refracting): 1

Step by step

Given: Refractive index n₁ (incident) = 1.5, Angle of incidence θ₁ = 30°, Refractive index n₂ (refracting) = 1
Formula: n₁ · sin(θ₁) = n₂ · sin(θ₂)
Result: Angle of refraction θ₂ = 48.59°

All results

Angle of refraction θ₂	48.59°
Critical angle	41.81°

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The physics

Snell's law describes how light bends when it crosses from one transparent material into another: the product of refractive index and the sine of the angle stays the same on both sides. Light entering a denser medium (higher index) bends toward the normal; entering a lighter one, it bends away.