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CH-27: Interference and the Wave Nature of Light. Owls, such as this long-eared owl, have eyes that can distinguish between two distant objects that are close together. This ability is related, in part, to the large pupils of the eyes and the wave nature of light, as this chapter discusses.
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CH-27: Interference and the Wave Nature of Light Owls, such as this long-eared owl, have eyes that can distinguish between two distant objects that are close together. This ability is related, in part, to the large pupils of the eyes and the wave nature of light, as this chapter discusses.
27.1 The Principle of Linear Superposition The beautiful iridescent blue color of the wings of this butterfly are due to the thin-film interference of light.
Coherent Sources Two sources are coherent if the waves they emit maintain a constant phase relation. Effectively, this means that the waves do not shift relative to one another as time passes. Lasers are coherent sources of light, while incandescent light bulbs and fluorescent lamps are incoherent sources.
Conditions for Interference Path Difference = d Sin(θ) For Bright Fringes: d Sin(θ) = mλ; m = 0, 1,2,3,… For Dark Fringes: d Sin(θ) = (m+ 1/2)λ; m = 0, 1,2,3,…
Example-1, Page 824 Red light (l = 664 nm in vacuum) is used in Young's experiment with the slits separated by a distance d = 1.20×10-4 m. The screen in Figure 27.8 is located at a distance from the slits given by L = 2.75 m. Find the distance y on the screen between the central bright fringe and the third-order bright fringe.
27.3 Thin-film Interference Consider a thin film of gasoline floating on a thick layer of water.
Colors in Soap Film A soap bubble is multicolored when viewed in sunlight because of the effects of thin-film interference.
27.4. The Michelson Interferometer An interferometer is an apparatus that can be used to measure the wavelength of light by utilizing interference between two light waves. One particularly famous interferometer is that developed by Albert A. Michelson (1852–1931).