Answer:
m=0, λ₀ = 522 10⁻⁹ m
Explanation:
In this case we can see that the first boy M The reflected light suffers an interference phenomenon, let's analyze what happens on each surface
* When light passes from a medium with a lower refractive index to a medium with a higher refractive index, it undergoes a phase change of pi rad (180º).
This occurs when passing from air to oil, but not at the oil-water interface.
* within the material the wavelength changes by the refractive index
λₙ = λ₀ / n
therefore introducing this into the constructive interference equation and assuming almost perpendicular incidence remains
2 t = (m + ½) λₙ
2t = (m + ½) λ₀ / n
λ₀ = 2t n / (m + ½)
light in the first order (m = 1)
λ₀ = 2 90 10⁻⁹ 1.45 / (1+ ½)
λ₀ = 174 10⁻⁹ m
the light for zero order (m = 0)
λ₀ = 2 90 10⁻⁹ 1.45 / (0+ ½)
λ₀ = 522 10⁻⁹ m
this radiation in the visible range in the green region
