Answer:
6.71×10⁻⁷ m
Explanation:
Using thin film constructive interference formula as:
2×n×t = m×λ
Where,
n is the refractive index of the refracted surface
t is the thickness of the surface
λ is the wavelength
If m =1
Then,
2×n×t = λ
Given that refractive index pf the oil is 1.22
Thickness of the oil = 275 nm
Also, 1 nm = 10⁻⁹ m
Thickness = 275×10⁻⁹ m
So,
Wavelength is :
λ= 2×n×t = 2× 1.22 × 275×10⁻⁹ m = 6.71×10⁻⁷ m
