A 4.0 × 10²-nm thick film of kerosene (n = 1.2) is floating on water. White light is normally incident on the film. What is the visible wavelength in air that has a maximum intensity after the light is reflected? Note: the visible wavelength range is 380 nm to 750 nm. A)380 nm B)420 nm C)480 nm D)530 nm E)601 nm

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Quizplus · Accepted Answer

For constructive interference in thin films, the condition is 2 * n * d = m * λ, where n is the refractive index, d is the thickness, and λ is the wavelength. Solving for λ with m=1, we get λ = 2 * 1.2 * 400 nm = 960 nm. However, this is outside the visible range. For m=2, λ = 480 nm, which is within the visible range.

A 40 × 102-Nm Thick Film of Kerosene (N = 1

A 40 × 10²-Nm Thick Film of Kerosene (N = 1