Transmission Coefficient
Fraction of wave power transmitted through boundary between two media.
Variables
Derivation
Energy conservation: T + R = 1. T = 4v₁v₂/(v₁+v₂)².
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: T = 0.96
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 Reflection Coefficient and before Group Velocity.
- 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 Transmission Coefficient formula?
Transmission Coefficient is written T = 1 − R = 4v₁v₂/(v₁ + v₂)². Fraction of wave power transmitted through boundary between two media. It belongs to Waves, under Wave Properties.
What are the units in T = 1 − R = 4v₁v₂/(v₁ + v₂)²?
In SI units, T is transmission coefficient (dimensionless); 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 Transmission Coefficient formula derived?
Energy conservation: T + R = 1. T = 4v₁v₂/(v₁+v₂)². The result is T = 1 − R = 4v₁v₂/(v₁ + v₂)².