Athin layer of oil of refractive index 1.30 is spread on the surface of water (n = 1.33). if the thickness of the oil is 210 nm, then what is the wavelength of light in air that will be predominantly reflected from the top surface of the oil?

546 nm

Explanation:

= Index of refraction of oil = 1.30

= Index of refraction of water = 1.33

= thickness of the oil = 210 nm = 210 x 10⁻⁹ m

= wavelength of light = ?

= order = 1

For reflection , the necessary condition is

nm

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