Topic: Electromagnetics
A plane wave E = 100 sin (ωt - 10 x) V/m in a loss less medium with μ = 4 μ0, ε = ε0 strikes another medium with 90 degree angle of incidence having μ = 9 μ0, ε = ε0, the reflection coefficient is:
- A. 0.5
- B. 0.25
- C. 0.1
- D. 0.2
Answer: D. 0.2
Explanation: η1 = √(μ1/ε1) = 2(120π) Ω, η2 = √(μ2/ε2) = 3(120π) Ω. Reflection coefficient Γ = (η2 - η1)/(η2 + η1) = (3(120π) - 2(120π))/(3(120π) + 2(120π)) = 1/5 = 0.2.