Reflection Coefficient
Fraction of wave power reflected at boundary between two media.
Variables
Derivation
From continuity of displacement and force at boundary. R = ((Z₂-Z₁)/(Z₂+Z₁))² where Z = ρv.
Your notes
Check value
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- v₁ = 2 m/s (Wave speed in medium 1)
- v₂ = 3 m/s (Wave speed in medium 2)
Result: R = 0.04
Where this formula is listed
- Waves formulas, under Wave Properties, alongside Period and Frequency, Angular Frequency, Wave Number, Wave Intensity and Intensity-Amplitude Relation.
- In the waves list it comes after Wave Speed on String and before Transmission Coefficient.
- Waves formula sheet, one of 37 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Reflection Coefficient formula?
Reflection Coefficient is written R = ((v₂ − v₁)/(v₂ + v₁))². Fraction of wave power reflected at boundary between two media. It belongs to Waves, under Wave Properties.
What are the units in R = ((v₂ − v₁)/(v₂ + v₁))²?
In SI units, R is reflection coefficient (dimensionless); v₁ is wave speed in medium 1, measured in m/s; v₂ is wave speed in medium 2, measured in m/s.
How is the Reflection Coefficient formula derived?
From continuity of displacement and force at boundary. R = ((Z₂-Z₁)/(Z₂+Z₁))² where Z = ρv. The result is R = ((v₂ − v₁)/(v₂ + v₁))².