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How to Calculate Snell's Law Refraction

What is Snell's Law Refraction?

Snell's Law describes light refraction at interfaces between different media. The ratio of sines of angles equals the ratio of refractive indices, explaining light bending.

Formula

n₁ × sin(θ₁) = n₂ × sin(θ₂)

Step-by-Step Guide

  1. 1Enter refractive indices of both media
  2. 2Enter incident angle θ₁
  3. 3Solve for refracted angle θ₂ using Snell's law

Worked Examples

Input
n₁ = 1 (air), n₂ = 1.5 (glass), θ₁ = 45°
Result
θ₂ ≈ 28.1°
Light bends toward normal entering denser medium

Common Mistakes to Avoid

  • Using degrees instead of radians in calculation
  • Confusing incident and refracted angles

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