(7%) Problem 6: A soap bubble is 110 nm thick and illuminated by white light incident perpendicular to its surface. TA D A What is the longest wavelength in nm which is constructively reflected, assuming soap has the same index of refraction as water (n = 1.33)? EY. Given data : Thickness of soap bubble, d= 110 nm = 110 x 10 m Refractive index of water, n= 1033. Incidence of light, 0- 90. . solution: Step L: For the case of a constructive interfe- Pence , We can calculate the strong reflection resing! 2 dosing = (m - = ) > Where, in is an order integer than represents other wavelengths that can be reflected. and a is the wavelength of reflected light. Now let us determine the visible wavelength with the most- constructive reflection, which is done through getting the Lowest- in value that yours a visible wavelength. we cam do by setting mel . A = 2x110 X 10 X 1.33 x sin 90 (1 - 0.5) 585, 2 x 10 - 9 M 585. 2 nm so, the Longest comelength, which is constructi- rely reflected is 585,2 nm. Am