Snell’s law
Snell’s law: use incident refractive index, transmitted refractive index, incident angle to the normal. Review the formula, worked example and calculation steps.
Inputs
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Formula & explanation
θ₂ = arcsin[(n₁/n₂) sin θ₁]
Variables & units
- Incident refractive index
- Numeric value · minimum 5e-324, maximum 1000000000000
- Transmitted refractive index
- Numeric value · minimum 5e-324, maximum 1000000000000
- Incident angle to the normal
- ° · minimum 0, maximum 90
Worked example
Use the displayed example inputs, then follow the substituted values in the solution.
Assumptions
Angles are measured from the surface normal. Total internal reflection has no real transmitted angle.
References
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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