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elica85
a light wave has a wavelength of 580nm in vacuum. suppose that a 7mm thick layer of water is inserted into one arm of a Michelson interferometer. how many "extra" wavelengths does the light now travel in this arm? by how many fringes will this water layer shift the interference pattern?
tip1: what is the wavelength of this light in water? tip2: what is the total distance the light has to travel in water? tip3: to be continued ;-)